Current bettas...
Raj is the biggest goofball. He LOVES playing. He's in a divided tank with my female Afia on the other side.
He'll plaster himself against the divider teasing Afia. She'll be on the other side of the tank flaring at him and he'll just be stuck to the divider I'm sure laughing if he could

heh
Also when I had mossballs in the tank with him, he loved those things. He would stare them down, then all of a sudden dart out at them and take off a small chunk of fuzz. He'd spit the fuzz out, watch as it slowly drifted down and then stare down the mossball again as if to say "Yeah, see what I did there! I'm bad!" Then when he got tired he would lay beside or on them
My female Afia is sorta strange. She's a piggy as most bettas are, but she will stare me down until I feed her. And when she spots me looking, she'll eyeball me, then look up at the top, then back at me, then at the top again hehe. She also used to do this thing where she would swim rght up against the glass and just got up and down up and down with her nose on the glass. I have no idea why
She loves watching & playing with Raj through the divider. I've never caught her doing anything goofy towards him though.
Marius is my curious fella. I just got him so haven't really had a chance to get to know his personality though, but I do know he was not shy.
As soon as he went into his tank, there was no hiding whatsoever. He looked around for hours, and whenever I got close to watch him, he didn't shy away at all, he'd come right up to inspect me.
I did have this really fast growing stem plant in with him. There used to be a bunch that would float at the top, and he just LOVED scooting through it. It all died though when we went on vacation for some reason so I had to throw it away.
My dearly departed bettas...
Caine was the biggest showoff. He knew whenever I was taking a picture b/c he would come right to the front of his tank and flare for me.
Bluebell was such a sweet fat girl. She lived in the community tank and absolutely loved cories. So much so that she would swim and rest with them. She also had a relationship with the ram as well. They too would swim and rest together.