Hizashi, aka Jonquil, was a crystal gem. He was in a relationship with Shota, aka Onyx.

His gem, a Jonquil gem, was in his forehead and similar to other gems he had a weapon he could generate via the gem. His being brass knuckles.

Jonquil had been minding his own business with Onyx while happily chatting with his one-eyed lover before they both heard something.

Onyx prepared for a fight and Jonquil got his brass knuckles out just in case.

Onyx: "Who's there?!"

Jonquil: "We're not gonna hurt you unless you give us a reason to."