Twenty years after Qin Zheng was expelled from his sect, he discovers that the junior brother he used to bully as a child has now become the sect leader. 

The only way to return to the sect is to go back in time and increase his junior brother's affection toward him.

But he only has ten chances.

Seeing all the affection points he painstakingly built up vanish after just half a year away -- reverting all the way back to square one -- makes him want to go beat up his younger self.

However, he ends up soul-traveling instead.

Just when he finally manages to return to the sect, he discovers... his junior brother wants to top him?

Qin Zheng: "Sect Leader Junior Brother! This kind of behavior is inappropriate!"

Qin Su, while leisurely undoing Qin Zheng's clothes, says, "I don't think there's anything inappropriate about liking to top my senior brother."

Well then -- still being the sect leader, still cultivating as an immortal, and now with someone to relieve his desires -- there really isn't anything inappropriate!

Bottom(shou) protagonist, younger top(gong)

Shameless former scoundrel shou x Upright and proper junior gong

The soul-traveling to the past is only temporary -- he will return to the present when time runs out.

P.S.: The gong has always liked the shou.