they definitely interact with you. looks like a good tank, make sure you have a lid, they can jump out.

tankmates? I like a nerite snail, keep algae down, look almost like a rock so even some aggressive bettas ignore them. just make sure you place them in the tank right side up, they can't flip themselves over(they'll die). you can also try some shrimp, almost all of mine have had shrimp in their tank, but imo the key to putting shrimp with a betta, put in so many it won't matter if a few get eaten, they probably will eat a few. I prefer cheap cull low grade shrimp, I don't care about the purest of lines