Acadian: Always, Jak and Arissa have been travelling for a few weeks now because they are going all across Skyrim performing these jobs for the guild.
Jak wants as much work as he can get so he can make money.
Fina definitely regrets not telling Jak earlier how she felt about him. They have been friends since their early teens so she has feelings for him, and he won't admit it to himself, but he does have feelings for her too. And yes seeing Jak with another woman that makes her see now that she shouldn't have waited.
Darkness Eternal: Jak is fortunate to have Arissa with him, he has developed a slight phobia of spiders after his last encounter in the cave where they killed the man who framed Arissa's parents.
He might

..... but Jak's main concern at the moment is making money so he can have a better life for his mom and him. Fighting vampires is at the bottom of his list of things to do. He couldn't care less about vampires and doesn't see them as a threat at this point because it's not like comes across them all the time.
Fina may be in pain seeing Jak with Arissa, but she would never do something to intentionally hurt Jak, like mess up his relationship with Arissa.
Chapter 9
Jak watched Fina enter the temple and then turned to meet up with Arissa, not being able to help but feel guilt towards Fina. He found her near the gate and the two left, and paid for a carriage to Solitude. Arissa questioned Jak on who Fina was as he had never mentioned her before, and he simply stated she was an old friend. Arissa knew there was more to it, but decided against pushing the subject as she felt it was not her business. A few days journey with few stops and they finally arrived in Solitude. The two of them approached Radiant Raiment and then went inside, Jak wanted to try something new so he had Arissa distract the two owners by asking questions about the merchandise and he quietly slipped upstairs and found
the ledger and changed the numbers. Returning downstairs without the owners noticing, and he gave Arissa a nod and she wrapped up her distraction and the two left. Jak was impressed with Arissa's silver tongue and how sly she was as he had seen her use that skill time and time again. The day was still early so they went ahead and booked a carriage to Windhelm to complete Vex's job. The carriage stopped in Rorikstead and Whiterun, so after a few days the two of them arrived in Windhelm. It was a simple job, and once inside the city they went to Candlehearth Hall and rented a room, and then later Jak went into the kitchen and
stole the golden necklace he needed out of a jewelry box. He questioned why they kept such a valuable item in the kitchen, but didn't mind seeing as it made it an easy target. They got some rest in their room and left Windhelm the next day and made the journey back to Riften. Jak turned his jobs in and Delvin brought up a special job he had acquired from a man in Solitude, Jak was to talk to a man named Erikur, apparently Jak's actions had made the Guild more noticeable in Solitude and so the man contacted Delvin.
Leaving the Guild, Jak and Arissa returned home to take it easy. Arissa loved spending time with Lanier and so they stayed for the day and left in the morning. Once in Solitude they made their way through the city to find Erikur who apparently worked in the Blue Palace, however this visit to Solitude did not go as planned when they were stopped by a guard who was eyeing them as he walked by.
"Wait.. I know you." "Excuse me? I think you have me mistaken for someone else?" Jak replied.
"No, there is no mistaking it. You are a wanted man, now you are coming with me!" The man grabbed Jak and pushed him against the wall, while Arissa backed up.
"Jak?!" Arissa was puzzled.
"Don't worry, just wait for me in the Winking Skeever..." The guard hauled him away to the dungeon. They took all of Jak's possessions and threw him in one of the cells, the imperial guard then came up and punched him in the stomach and
threatened him before leaving. Jak couldn't do anything but wait and after a few days the guard came back and said that he was free to go; upon asking why the guard mentioned that someone had paid to have him released and it was none other than Arissa. She was waiting for him when he left Castle Dour and he thanked her and gave her a hug, "Now what do you say we finish this job and get out of here?" He whispered to her.
They went to Blue Palace, but one of the guards told them that Erikur had gone home already so the two of them went straight to his house. They knocked on the door and told him Delvin had sent them so he immediately let them in.
"So Delvin sent you did he? Good, I have a very important job for you. The Captain of the Dainty Sload and I had an agreement, but he has decided to break that agreement and so now I want him out of the picture. I want you two acquire some Balmora Blue, and plant it on the ship that way the Captain will be arrested and I no longer have to deal with him."
"Where do we get the Balmora Blue? That is illegal in Skyrim last I checked." Jak was curious.
"Ah yes. There is another ship docked here called the Red Wave, talk with Sabine Nytte she will be how you get it. And make this fast, Captain of the Dainty Sload is here in Soltidue and I want the guards waiting for him when he returns to his ship."
With all the information they needed Jak and Arissa headed down to the Solitude Docks and found Sabine on the Red Wave.
When asked about the Balmora Blue she assured them she had it and that she was the only way they could get it and therefore wanted them to pay 1500 gold for it. Jak refused to pay that and Arissa pulled him aside and convinced him it was the only way and he agreed and reluctantly handed over the gold. Sabine gave Jak a key and told him it was to a chest that had the Balmora Blue.... but it was under the docks in the water. Jak was not happy, but the two left the ship and he took his armor off to jump in the water, Arissa enjoyed every minute as she found Jak cute when he was mad and teased him when he was practically naked.
He jumped into the water and swam to the bottom and found the chest, he unlocked it and grabbed the Balmora Blue and came back up to the surface and got dressed. With the Balmora Blue in their possession they headed past Solitude along the road to find the Dainty Sload which was a good distance away near the Solitude Lighthouse.
They crept near the ship to find one crew member patrolling the deck while one sat drank away his misery, so they quickly sneaked by and into the ship. Jak suggested Arissa wait by the entrance so they wouldn't be as conspicuous, and she reluctantly agreed and waited by the door to be able to catch any crew members by surprise should they enter the ship. Jak made his way through the ship avoiding all the crew members that were walking around, until he came to the bottom of the ship and was forced to kill one of the crew to get by.
He came up behind him and slit his throat and quietly laid his body on the floor as to not alert the other shipmates. A little further there was a chest that was the perfect place to put the Balmora Blue,
so he picked the lock and placed it in and then turned around made his way back out.
He was surprised by how oblivious the crew was, and when he told Arissa she joked about how they were most likely drunk. It was now early in the morning and Erikur had returned to the Blue Palace to start his early daily duties, he was glad to hear of Jak's success and said that the guards will most likely have the Captain in jail before lunch.
He then told Jak if Delvin needed anything in Solitude he need only ask. The special job was complete and the thief duo returned to Rfiten.
Jak leaned against the bar and told Delvin of his success, and Delvin even cracked a smile and congratulated him. "You're doing a great job mate, we had a new merchant move into the Flagon while you were gone. If you keep this up we will be back to our glory days in no time." Jak patted Delvin on the back and then was called over by Vex who told him there were rumors that a special job request was on the table for Windhelm, but the person wanted to make sure the Guild was definitely making a comeback so she gave another job in Windhelm.
After finishing up his talk with Vex, Jak and Arissa returned home to celebrate their triumph with the Guild.