You and I Will Be in Love for Three Lifetimes

In the first life, he saved her, helped her get revenge along the way, and protected her. In the end, he was wiped out for her. He said, remember to pay back what you owe me. In the second life, he found him and he already had a sweetheart. He helped him and tried his best to save his sweetheart. However, he died in love with his sweetheart in front of her when she was at her weakest. In the third life, she followed him since he was born. She said, in this life, your childhood sweetheart can only be me!