Namjoon: Namjoon would find it to be really cute and special, and he would laugh softly as he nudged your shoulder gently to point at the small butterfly sticking to your sleeve. You two would both fawn over it, and you’d even nickname it “Buddy” and pretend as though he were your son. You would walk around a bit more afterwards, careful to take care of Buddy until he made the decision to leave on his own. Namjoon would probably enhance the joke by dropping to his knees and dramatically mourning the loss of your butterfly together, and it would make you two closer.
Suga: Suga would literally turn into a child in front of your eyes, he would get so excited that his entire face would just light up with happiness and his mouth would widen to form a broad smile. He would be so happy that a little butterfly had decided to rest its wings right on your hand, and he would be taking selfies and pictures of it which would leave you laughing hysterically. He would find it to be really special for some reason, and he would fall in love with how endearing you and the aspect of a butterfly landing on you was. His enthusiasm would crack you up.
Jin: Your situation with Jin would be another story because the two of you would first find the butterfly to be adorable and special, however the little thing would refuse to get off your hand and neither of you would have the heart to force it to leave. You would take it around with you all day, and despite how careful you had to be not to harm it, you would both grow so attatched and it would truly be a crazy and wonderful time. Jin would even want to take a picture of you two together to comemorate that afternoon, and he would be a little jealous because he would be the one who wanted to hold your hand.
J-Hope: J-Hope would get excited just because now the two of you had another friend! you guys would be at a wedding together in the summer, having decided to play hide and seek with the other members. You and him would have paired up and chosed to take a stroll in a garden, hiding behind the multiple and thick bushes when suddenly, a little butterfly attatched itself to your shoulder. He would gasp and step away, shaking his hands as he exclaimed that it was a sign of good luck and that you two had a high chance of winning.
Jimin: When you two went to the zoo together and visited the butterfly garden, Jimin would be so excited as he described that he couldn’t wait to hold some butterflies close and examine them. He would have been talking about it all day, yet when the two of you entered, an entire flock of the insects would fly right on you and he would be bare of the multicolored wings. You two would be hysterically laughing at how rejected he was, and you would offer him a few which would make him feel better and realize how sweet you were.
V: I think that V would be the only one a little afraid of the insect just because of the position that it was in and the fact that it just freaked him out. It would be more of a brown moth, and the thing is that it would attatch itself to your face and he would shudder at the sight and be torn between helping you because you were also scared and running away. He would gently shoo the insect away with shaking hands as he yelped from fright and grabbed your hand, leading you away at a full sprint as he whined about the experience of touching the fluffy creature.
Jungkook: You and Jungkook would be on a date at the park, and you would be wearing a very pretty orange and black top. You would have done a lot of things outdoors, but when it was time to stop at a cafe to have some lunch and refreshments, he would be closely inspecting the fabric to realize with a confused expression that there had been a butterfly hanging on to your shirt the entire time! He would bring it up and laugh softly, telling you that you two hadn’t been alone on your date after all, and while holding hands, you guys would release it outside.