How does Giriko's 'Time Tells No Lies' Fullbring work?
Judging by the way he states it, he can create "contracts" with set time limits.
The contracts seem to extend to anything and everything with a spirit.

as the fullbringers state "Everything has a soul". he makes a contract with the box to trap ichigo inside, the next is the energy, he makes a contract with the air to fire it at rapid speeds (energy) at ginjo, then finally after he is wearing his fullbring he makes a contract with his own body to become "invincible" as he states...

"Time tells no lies"
ie, within this set time period everything I say is true.

I don't have much to back this up with, it's just as logical as I could think of.