Barajou no Kiss

Everything About Fiction You Never Wanted to Know.
Anise and all her boys, not that she wants them.

Title Translation: Kiss of the Rose Princess

So you think your father is a manipulative bastard out to ruin your life? Anise Yamamoto would like to compare notes if you wouldn't mind.

First her father straps her with a choker that won't come off and he claims is a amulet of protection. When said choker finally does come off (through no efforts of her own) she finds herself saddled with four teenage boys calling themselves her 'Rose Knights,' who use her blood to fuel their magic, a vague prophecy of doom, and then her father decides to come home.

Anise can summon the boys via color coded cards and order them to do her bidding. They must do what she says or get beaten with rose thorns. Downside to having a quartet of hot guys who have to do your bidding or face rose thorns of doom is that said magic is powered off her blood. (This is strongly implied to be the only reason Anise doesn't run around trying to take over the world.) Her father is trying to replicate the Rose Contracts for reasons unknown and likes to mess with Anise's head on the side.

This would be your bog standard Shoujo manga except for the Author's fondness for subverting, inverting, and genderflipping Shoujo norms.

Tropes used in Barajou no Kiss include: