Space-timecontinuum Stories

At the age of fourteen, Ethan is a boy trying to make his father disappear from all universes, though it would likely create a tear in the multiverse. When he saves another universe jumper, he becomes afraid that she will stop him. When trying to figure out if he can trust her, he finds himself falling for her. Will he succeed or will his new friend stop him? I like this because the main character is the villain, which you don't see often.