You sleep over for the first time:

He was very tense about it. He kept in the corner, afraid to make any moves that will make you feel uncomfortable. He was also kind of embarrassed as he doesn't have much to offer as he just lives in the woods but he still offered anything he could.

Both made dinner together, which was a nice activity that worked to ease the tense and awkward air. Once night came both laid outside and stargazed, holding each other, softly talking about light topics. Once both so exhausted both moved back inside, where both continued cuddling and fell asleep in each other's arms.

When you hold out your hand without saying anything:

Can't possibly want to hold his disgusting hand so he just gives you the closest thing, only to almost flinch when you toss it aside with a disapproving look then snatch his hand. It is as if you read his mind and now non-verbally said "Your hand isn't disgusting, give it here because that is what I wanted!". Makes him feel nice inside.

When you help him button up his shirt:

He doesn't do this stuff much, and little precise things are hard as he has big hands so you'll help him with it. He's mainly busy on being annoyed by how uncomfortable such shirts are and complains he wants his tank top back.

Your shoelaces are loose:

You suddenly stumbled so he caught your arms then crouched down and tied them for you. Immediate snap sounds as Mary appears to capture every angle of it, fangirling of how adorable and if her man doesn't do this for her she doesn't want it. So of course Vin Jin made a snarky comment to it, which got him an elbow in his ribs.

When you have to study/focus on work:

No problem, that is why you are even here. He is silent, the nature is peaceful, and the atmosphere is right. It is perfect setting to finally get some work done. He doesn't interrupt once, sometimes looks over and admires your focused expression then goes back to his thing.

You spill juice on his couch:

Doesn't matter, he got that couch from somewhere random anyway. That juice isn't its only dirty spot anyway. Which is why many won't sit on it as no one is sure how those spots got there... Mary already lectured him that he needs a new couch, especially if he is gonna start dating.

It begins raining so your white shirt becomes see through:

He glanced to you then immediately ahead, eyes widen, his cheeks becoming a soft red. When you asked what he shrugged off his jacket and draped it over your shoulders, mumbling "Nothing". He's not gonna point it out and make you feel embarrassed but he will still take care of you.

You take him ice skating:

Finding shoes for him was the true issue... But once you found some both went on the ice. And damn, he looks like a newborn animal trying to walk for the first time. Legs shaking so much, hands held out for balance but failing so he just held his hand to you so you grabbed it and helped him. Eventually he could do it but he didn't have the confidence and that's a major factor so he still kept doing it stiff and awkward.

If you are a single parent:

First meeting your kid was eyeing his extra fingers without even hiding it. You told them to stop it but Seongji assured it's fine, since he knows it is abnormal and expected this.

He didn't want to scare them so he crouched then held his palms out, asking if they want to touch it. He's not sure how to handle kids but he will try.

So he mainly just lets the kid lead the moments and goes along with it all. When they cry he is hesitant to comfort them as he isn't the father but will crouch and softly assure them. If they misbehave he steps back, now definitely not wanting to overstep any line and insteads goes to find you.

When someone interrupts the date:

Silent but deadly. He looks to the person very slowly and just stares at them, no words, just an unreadable look yet the annoyance is radiating off so the person nervously leaves as that is how one ends up in the hospital. Seongji just continued the date without word about it.

If you have a tattoo:

He took the area, pulling it closer to inspect, then traced it softly, as if to make sure it is real then asked why you chose this. As you explained he listened while examining all the details.

If you smoke:

He doesn't care much for it. If you want to ruin your lungs you go ahead. At times he might put it out if you do it aside him, telling you it smells awful, is terrible for you, or that he doesn't want to inhale that.

Someone starts filming you and being inappropriate:

He grabbed the phone over the lens right away, glaring at them, telling them to get lost before he breaks it. They did not, and so he broke it in a simple clench. With that anyone would be freaked out, so they scurried away, satisfying him.

If you make his clothes:

You are the only reason he has clothes besides his typical attire. You mainly began doing it as he began smelling so bad as he only had that pair of clothes so now he can switch and properly wash and let the others dry. He looks forward to your visits as he always hopes you'll bring some new clothes with you.

When you make something artistic that represents him:

He was touched. This made him see himself in a slightly different light. It touched him. He will even ask if he can keep it. If he can he hangs it up in his place so each day he can look at it, feel appreciated and while still feel abnormal also unique and special.

When you fall asleep on his couch:

We already clarified that couch has dirty spots of unknown cause, so he will scoop you up and just carry you around as you shouldn't lay on such a thing. Or he will lift you, lay on it instead, and put you on him.