I do a lot of writing and named both my bettas (past and present) after two of my characters.
Kio was a kind fella with an extremely loving personality, just like the 'person' he was named after. Daichi, on the other hand, is an extremely narcissistic and aggressive...again, much like my character.
Their colors also played a small part in their names:
Kio was red, character has red hair
Daichi is blue, character has blue eyes
Oh, here's the translations for there names just for fun:
Kio ( 気男 ) - male spirit (loose translation)
Daichi ( 大智 ) - great wisdom
(names make more sense if you knew the story, they're both 'ironic')