Wait because I never thought of them as poly/team up... (if you're asking all of them together)
But I have some thoughts about them, I imagine Cindy being super jealous and possessive, especially if someone flirts with you, and it would be so much worse if you two were in an official relationship, she straight up confronts you and keeps asking "Oh, so you think they're pretty?" and tries to get your attention a lot (she likes to have your attention)
I see Eloy being protective, worried and really caring, super scared of losing you and prefers you being at his side, in his sight, thinks about you all the time and needs to know how and where you are, you're the only thing that matters to him, and you are his priority
I can't really say much about Alê, Franco and Caio, but I'll try
Alê is the more quiet, observer type, he likes to watch you, study you and keep you company, maybe he talks a little when he's with you, but like, really little, two or three words, the fact that he's a yandere wouldn't be obvious, unless you noticed something different or weird about his behavior
Franco is kinda shy around you and admires you a lot, I feel he gets jealous when someone flirts with you, and maybe... just maybe he imagines burning anyone who hurts you, he feels weird when he thinks about that, it's the same feeling he feels, of wanting to see the world burn, but mixed with something else
Caio likes to tease you, but you have a special spot in his hearts, it's obvious to everyone, he also isn't one that doesn't look or seems like he's obsessed until you notice some weird patterns about his behavior
Things are way easier to them if you are a member of the band or someone that works for them, because you would be next to them, and it would be easy to keep an eye on you, maybe it would also be easier to manipulate you or isolate you since they are close to you and would know everything about you
If you were a fan, it would be kinda harder, but maybe if you were like these super fans that would do anything they say, it would be also be easy to manipulate and isolate you, keeping you with them
Oh, and of course, their behavior change when they are using their mask
(EDIT: I THOUGHT I HAD POSTED THIS WHAT.)
