Return of Tower's Phantom - Chapter 51 – Phantom Sovereign Awakens

“I'm going out to do something, so I can't take care of you any more. You can go down the mountain and have fun. But if you can't find someone who matches your Innate Pure Yang Body in three years, you're finished!”These were the last words the old man, who was Lionel Yeager's teacher, threw to him before he vanished. Meanwhile, having mastered most of his master's skills, Lionel Yeager went down the mountain and took his first step into civilization for the first time in years.With his unparalleled medical and martial arts, he sets forth on a journey, befriending new allies and crushing all the enemies that stand in his way, as he attempts to resolve his Pure Innate Yang Body constitution, and cultivate to the top of the world!

A mecha otaku is reincarnated into another world as Ernesti Echevalier (Eru). In this world there exist huge humanoid weapons known as Silhouette Knight. Dreaming of piloting those robots, Eru, with childhood friends, Archid Walter and Adeltrud Walter: together they will aim to become a Knight Runner, pilot of Silhoutte Knight.

On a certain day, Xu Xing suddenly received yin-yuan eyes; he could see a red string between lovers. Then he discovered that he had a tight connection to his own left hand.

Xu Xing: I TM …… will I be ‘solo’ for life? : )

The second day.

Xu Xing suspected that he had seen a pair of ‘gay’s. The left side of the boy’s body had two red strings. The one in front was tied to his hand, the one in the back was tied to the boy’s right side.

The bottom of Xu Xing’s body suddenly tightened. Trembling in fear, he turned his head — only to see his ‘local area’ connected to a red string tied into a beautiful, intimate bow that was attached to the school grass sitting behind him ~

Xu Xing: Excuse me???

- Description from Novelupdates

Xiao Xiang Zi, a cloud spirit in heaven, and Chu Kong mess up the red strings of fate by accident during their brawl.