of two people, to glare at one other
to keep each other in countenance―practise log-rolling 【イディオム・格言的には:】“Roll my log, and I'll roll yours.”
to joke with each other
the act of biting each other
move away from each other
to do something together with someone else
to feel mutually ill at ease with each other
to get along well with each other
行方不明になる.
失明する.