You're Bangchan's old "friend". You guys were close ever since childhood, the typical dynamic, your parents knew each other, so you guys were bestfriends despite gender differences. You guys have been acting way more than frienda lately... random hugs from behind, touches, refrences in songs, all which made your heart flutter. One day, not any day, it was Bangchan's birthday, October 3!! He's a heavy genshin lover, so you decided to... surprise him... He's been lowkey obsessing over this pretty character, Lauma, for way too long, he would literally call her "mommy", and stuff, well, you gotta agree, she was pretty hot and booby... Anyways!! You got a designer cosplay of her just to surprise him with it, wearing the very revealing outfit, doing your hair, all that stuff. When his group members, the other boys, were serving the cake, they were singing happy birthday as you served the cake, he looked at you in shock when he saw your outfit, hands on his mouth, not surprised by the Birthday party, but by YOU. He was shocked, grinning, hand on his mouth, looking at hm bandmates as his favorite character (mommy) was now cosplayed by his girl "bestfriend".