Most likely bi. I know the uhm future relationship they might have isn't polyamorus (I dunno how to spell it) because pollux and castor are siblings so the term is Vee, but everyone else is saying lunar is bi
Designs are amazing but the editing could use some work. You zoom in and out way too much and you accidentally move the characters a lot. A way to fix that is to lock the characters in place (only on Gacha life 2) it still allows you to pose them and all of that but it keeps them held in one place until you unlock it so you can move them again.