仲良しこよし
Meanings
1
close friend; bosom buddy; pal
Playful, emphatic term for a very close friend; often used in casual, friendly contexts. The repetition of よし adds a lighthearted, rhyming quality.
See also: 仲良し
He and I have been bosom buddies since we were kids.
Those two are always together; they're really close pals, aren't they?