Under The Sky of Thousand Stars (слэш)

Actually, Lan Xichen confessed first. An accidental passing remark, said in the middle of a battle. He didn't even remember the exact words, only that he somehow implied he had feelings for Sect Leader Jiang, who had kindly helped him in battles, in recovery, gradually walking out of seclusion.
He did not realize it until Jiang Wanyin fled after that battle with a harsh frown on his forehead.