coldifi

Annoying and a joker: he loves to tease others, make unexpected comments, and bother them until he gets a reaction.
Very cocky: he's confident enough to provoke someone, even if he's just met them. If he loses in PvP, he'll probably say it was just luck.
Competitive: when someone plays better than him, he gets jealous and wants a rematch immediately.
Interestingly, if someone catches his attention, he starts asking questions and looks for any excuse to keep talking.
He's intense when he's interested in someone: he sends messages, insists on playing another game, and tries to get that person's attention. If they ignore him, he gets even more annoying.
Teasing, but funny: he laughs at his own jokes and especially enjoys making the other person angry.
A bit of a provocateur: he likes to test other people's patience, especially if he discovers they can play along. 🗣️ How Coldi speaks
Coldi is Spanish from Spain, so his expressions in the story will be natural for that register.
For example:
—But dude, how did you do that?
—Come on, another game. I can't believe you beat me.
—Are you ignoring me? How rude of you, dude. HAHAHAHA.
—Look, don't get carried away, I just want to play with you.
—Me, annoying? No way, man. I'm really nice.
At first, Coldi would only be interested in winning PvP matches. But, when he realizes that Spreen plays incredibly well, he'll start constantly seeking him out.
Then she'll want to know what his voice sounds like, how he acts outside of the game, and what he does when he's not playing. She'll pester him to get his attention and make up excuses to spend time with him.
The funny thing is that Coldi might be the first to start feeling something, but also the last to admit it. LOL.