Why Did Gotenks Boo Acknowledge Tenshinhan

[Yoshi]

It was impressive that Shin Kikoho deflected Boo’s ki attack but I never understood this.

 

[Papasmurf]

To make Cocoman's panties wet

 

[SSJ2]

Gotenks Boo knew that with 7 years of extreme training, Tenshinhan would have been able to vaporize him with a singular Shin Kikoho. He could foresee that a fusion between Goku and Tenshinhan would have been invincible. Tenshinhan is the third unnamed top master of the universe referenced by the Boss Old Kaioshin.