I Became the Absolutely Conquered Heroine of a Dating Sim

Synopsis

Kim Siyeon was my favorite heroine. She was also the easiest one to win, the tsundere who fell for the protagonist on every single route. Then I woke up as her. Twelve years before the game even starts. Fine. I'll just stay far away from the protagonist and never fall for anyone. ...So why is Han Seojin already sitting next to me on the daycare bus?