Please Don't Tell My Parents I'm a Giant Monster

When an evil artifact offers you the power to turn into a monster, agreeing would be stupid. Mirabelle isn't stupid. She also doesn't have much choice. Her friends all have super powers that let them go on exciting adventures. Mirabelle's super power is to be made of glass, and walking across a room is dangerous enough.\nBut the shiny rock won't shut up, and to get rid of it, she has to use its powers against it. She does that carefully, because Mirabelle isn't stupid.\nUntil Mirabelle falls in love, and love makes everyone stupid.\nNow supervillains and superheroes are fighting over four pieces of the Heart of Vermiel, and a girl who breaks if she runs has to collect them all, or be broken. She has to turn into a monster on the outside without turning into a monster on the inside. Somewhere in this mess there has to be an ending that lets her stay alive, stay a good person, and maybe get a chance to run, and be angry, and break things just once.\nBesides, how many girls can say their boyfriend is a dragon?