The Sword And His Shield (слэш)

For a moment, a small, elegant woman in green robes who Shen Jiu now knew as the Qing Jing Peak Lord had tilted her head towards him, seemingly taking an interest in him just like Yue Qingyuan said she would -
And then a gruff, deep voice said, "Sure, I'll take him," and Shen Jiu looked up with horror into the dark-eyed gaze of a massive seven-foot-tall swordsman with a faded scar on his face from eye to lip.
The Bai Zhan Peak Lord, Xu Ningchen.
And Shen Jiu's new teacher.
*
Against all reason and sanity, Shen Jiu ends up on Bai Zhan Peak as its newest - and most recalcitrant - disciple. Somehow things end up working out anyhow, especially when he makes friends with a brilliant young prodigy who seems to need his companionship as much as the other way around.