time for the princess to SHINE
1) she CAN drink blood but its not nutritionally necessary. she drinks it like someone whose parents let them have a glass of wine with sunday dinner.
2) Crown Jewel is more of a nuisance than a real threat to Flurry and his position. the truth is that crown jewel has no real claim to any thrones, shes at the very end of a lot of lines of succession and literally the sun will burn out before she has the chance to seize any power.
3) they are THE bullies ever. luster, crown jewel, and Valkyrie all grew up together and luster and jewel literally made vals life a living hell. luster would mostly stand to the side and say 'YEAH' like silver spoon while crown jewel would tease valkyrie for literally being alive. really both luster and crown were jealous and insecure, and val was an easy target for their unchecked attitude problems.