I’ve Waited for the Fairy Teacher for Hundreds of Years

“Warning: Yaoi content: This manga contains materials that might not be suitable to children under 17. By proceeding, you are confirming that you are 17 or older.”
I’ll wait for you for as long as forever. Fairy Teacher Xing Li is on a mission to seal an evil relic when he falls into the Mortal Realm and loses his memory. Nuo Qing, his self-proclaimed disciple, takes him home. But only when an old friend visits does Xing Li realize that Nuo Qing has been waiting hundreds of years for him?