My two bettas just got new homes. Beethoven's tank has been relocated to my bedroom and I just brought by other one home yesterday, so they're still adjusting to being near each other. My new fish just spotted Beethoven and started flaring at him. Beethoven looked right at him, turned, and leisurely swam away like, "...Not impressed". I giggled a little. And now new guy is flaring and dancing again and Beethoven's just completely ignoring him.
I'm glad the new guy's flaring, though. I'm hoping that means he's starting to feel comfortable in his new home. Yesterday and this morning he was showing his stress stripes and seemed quite ill at ease. Maybe he's starting to get settled now.