So, this is basically where everyone has a gemstone/ is a creature called a Gem. they are basically aliens and can summon weapons and do fusion. 

Fusion is basically two gems do a dance and they both physically turn into light and their forms combine into a new gem. Say a pearl and an Amythest fuse and become an opal. 

Scenario 1-

You and (Y/C) (your crush) do an accidental fusion and are trying to figure out what/who you are. 

Scenario 2- Or make one up!