Accidentally Winning You Over (Harry Potter)

Percy Chester was hailed as a dream pastry chef and called a maker of happiness. Ironically, he was an abandoned orphan who had clawed his way up from the very bottom of society by even the most sordid means. So he never ate the desserts he made. He loathed his own existence, yet longed for someone to care about him. A car accident took his life, but also gave him hope. He was reborn into a warm, bustling family. Strangely, he had the same first name as in his previous life, but a different surname: Percy Weasley. Reborn, he cherished his family and worked hard to grow stronger. When he was eight, an uninvited Potions Master opened his eyes to a whole new world. Percy studied under him with all his might, and unwittingly became one of the few people with whom the Potions Master could talk...

Severus Snape had lived in Spinner's End since childhood. He had witnessed the darkness of the Muggle world, and had become part of the dark side of the wizarding world as well. He had immersed himself in darkness. Apart from the conviction that he must protect Lily's child, he had no other reason to keep living, no other hope. Then, by chance, he met eight-year-old Percy Weasley. As they grew acquainted, Severus unknowingly drew warmth from Percy, and before he realized it, Percy Weasley had become another pillar in his heart. But with his abysmally low EQ, Severus failed to notice until an unexpected incident...

PS: This story revolves around Percy and Severus. Severus is the top and Percy is the bottom. If you don't like BL, please move along.