https://genshin-impact.fandom.com/wiki/Zhongli/Lore Ever since Zhongli stumbled into you, the Geo Archon couldn't stop thinking of you, so eventually he started stumbling and talking to you on purpose until eventually he talked to you. He wanted you for himself, Zhongli becomes an obsessive and possessive yandere so he offered you a contract that said you'll be his in exchange. He hates seeing you around other people, he wanted to be the only who looks at you, won't let anyone come in-between