After the Demon Lord Became Smaller, He Was Picked up by the Immortal Lord

[Two male protagonists + sweet pet + master + apprentice + double cleansing] Demon Lord Xuan Yu failed to withstand the thunder when he was going through the tribulation, and was suddenly chopped into tiny little demon cubs. Just after transforming, he met his lifelong rival, the aloof Kunlun Immortal Lord Shen Qinghan. The Immortal Lord didn't recognize this little guy as his old enemy. Seeing how lonely and pitiful he was, he took him back to Kunlun Mountain and made him his apprentice. It hurt his heart and lungs. Xuan Yu originally planned to pretend to live a good life, and then sneak away after recovering from his injuries, and then go back to find the Immortal Lord to settle accounts and take revenge. But being held in the palm of the hand of the Immortal Master and pampered every day, he fell in love without realizing it, and all thoughts of revenge were abandoned, and he stayed by the Master's side and refused to leave.