Location: Lotus Lake
Prerequisite: Complete Prelude to Counterattack; see below
Petitioner: Ye Fei
Reward: None

In order to trigger this quest you need to complete the entirety of Leng Wuqing's storyline, which culminates in Prelude to Counterattack. Once you've completed this quest you'll receive a small hint at where to go next: Lotus Lake. (Note that you should not complete the main story quest At Xungu Pass before doing this, as this quest seems to lock out the possibility to recruit Ye Fei.)

Travel to Lotus Lake. It's located east of Wild Boar Woods, to the south of Luo Village and Wutong Village. If you check the south end of the area - which is small, so this won't take long - you'll trigger a cut scene with Ye Fei, bodyguard of Lou Fuzhou. He spoke of burying Fuzhou's body, and he's here honoring the request...

... only to be interrupted by a pair of warriors. They plan to dig up the corpse, and Fei isn't going to let that slide. Neither, apparently, is Yi.

Li Huaixi and Zhang Hongyan

This battle is a bit of a challenge if you came here right after dealing with Lou Fuzhou. Li Huaixi and Zhang Hongyan are both capable warriors, and you only have Yi and Ye Fei on your side. You also can't control Fei, making him a bit unpredictable. Huaixi and Hongyan attack as follows:

  • Huaixi is a saber fighter, and favors a mixture of short- and long-range attacks. It's difficult to stay outside his attack range.
  • Hongyan is a fistfighter, though he has several AOE attacks that hit at a considerable range as well. 
Both enemies are a fair bit stronger than Fei, so while he'll distract them for a bit Yi is on his own for the majority of this fight. Try your best, but you probably won't be winning this battle - and you don't have to, either. A mysterious third party will drive them away.

After the battle Ye Fei will express his appreciation for Yi's help, and offer to return the favor. From this point on Fei will remain at Lotus Lake, and you can Invite him into the party. He's already at 60 Affinity, so you're good to go. (Oddly enough, you can't give him any Gifts, so... good thing he's already prepped to join the team.)