Witer's Nightmares
The first quest involving Witer is unlocked at day 6, provided you can access the basement (by starting "Hakan's quest to get buzzed - part 2" but not necessarily finishing it!) (it was changed from before, it's useful if you need the skill unlocked here for that boss, especially for high INT builds!).
Witer will feel sleepy when you try talking to him, he does look very cute, but he has a problem, obviously. After you try talking to him a second time, you will be able to ask Meko (the horn in the cellar) about him, and he will tell you Witer comes out of his room and stays crouched in a corner of the cellar, every night, from 3:00 to 3:55. Once talking with him, you will have to face a ghost just outside of the tavern, only from 3:00 to 3:55, but you won't be able to hurt it in any way. Note: Witer is supposedly sleeping in your room until you defeat the ghost, but he doesn't actually show up there. Also, if you didn't hug him in the cellar you don't deserve his love :p.
Go back again to Meko, who can teach you your first magic skill! This is your only way to deal damage to ghosts for now, so use your "holy fist™" to win. This magic skill is very powerful, so 2 of them should be enough to defeat the ghost, bring a MP potion just for safe measure. The quest was slightly altered after the addition of fire bombs, since those also work against ghosts: some dialogue changed, and Meko teaches the holy fist before attempting to fight the ghost now.
Note: escapes are always guaranteed against ghosts, even random ones you can encounter south of the tavern, where you fought the demon and in the forest west of the bull tribe, only during the night, after completing this quest
If you lose, you get a kinky CG scene, but you don't want that, right? Witer needs to sleep before he goes crazy. When you win, sleep and tell Witer you won, and he can rest easy now. You get 1 level up point, nothing else, but you did learn a new cool skill and saved a friend from madness, or even from dying.
After this quest, and after 3 days have passed, Hakan will wake up and get back to his favourite table 😄 but let him be, he is still hungover.