How to Not Get a Girlfriend
Severus had hoped that Lucius wouldn't be too upset, but he knew his hopes were futile. One poorly timed prank had led to lucius’ favorite book being ruined and Lucius wasn't quick to forgive. He decided that the best way to get back at Severus was the only person he truly cared about.
Lily Evans.
He wanted to hurt Severus as much as possible, so as the weeks passed after the prank he slowly got closer to Lily, being kind to her, bringing her gifts, anything that Severus had told him about her before he used to his advantage. One day after he slowly got lily to fall for him, he kissed her, in front of severus, as deep as a kiss can be between two teenagers can be, and the very next day he spread rumors about how awful of a kisser she was, how her breath smelled of rotten fish and tasted even worse, how when looking up close she had disgusting pimples and that if he were her he wouldn't ever show her face anywhere. He broke her heart, and told everyone it was Severus and said he was the one who started the rumors because he was jealous of Lily and wanted Lucius all to himself, and how he had told Severus to stop because it would never be that way between them.
Lily couldn't face Severus after she heard that he was the one spreading the lies, and so their friendship ended, and at the same time Lucius ghosted him, so Severus was completely and totally alone. This really made him look at his life and really see that he didn’t want to have awful friends like lucius anymore, so he started working on being more extraverted and outgoing and he started making better friends, as he bettered himself lily eventually found out that severus never said anything about her and learned that everything was lucius’ doing and that he had set everything up to get back at severus for an accident and she eventually stopped talking to him and rekindled her friendship with severus.