A Princess's New Life: Sonic reverse harem story

Four anthropomorphic hedgehogs from Mobius join an inter-species cultural exchange program on the earth, which is held to be familiar with newly discovered human-animal hybrid or liminal creatures. Ironically, the four hedgehogs finds out that their real task is something else, and that is to protect the half-hedgehog princess of those liminal creatures, Sierra Star, who seemingly is a small human with hedgehog traits and targeted by her enemies. Can the anthropomorphic hedgehogs handle living with a humanly princess hedgehog?
Pairing: OC Sierra x (Sonic, Shadow, Silver, Scourge, Mephiles, slightly with Knuckles, Manic, Metal Sonic), OC evil Sierra x (Mephiles, Venice, Infinite). Rated M for violence, harem relationship and Humanoid x Anthropomorphic lemon scenes. Inspired by 'Monster Musume'.