I Can't Believe I Became the Heroine's Little Sidekick

Su Mengyao hates Lin Wan. She's the reason Su Mengyao was humiliated, and she'd love to kill her. So why does she eventually become Lin Wan's little shadow? No, not her shadow. She's just secretly learning Lin Wan's skills. She's definitely not following her around. But why is Lin Wan so different from everyone else she knows? (Dual female leads. One is a villainess. No rebirth, no transmigration, no comments from readers. The villainess awakens entirely on her own.)