hobby friend; friend through shared interests
Colloquial noun for a friend made through common hobbies, tastes, or personality. Often used in casual conversation, especially among younger speakers.
See also: 類は友を呼ぶ
We share the same hobbies, so we quickly became hobby friends.
It's easy to find friends with common interests on social media.
Abbreviation of the proverb 類は友を呼ぶ (birds of a feather flock together). The exact origin as a standalone noun is uncertain, but it emerged in colloquial speech.