Cosmo always sacrificed for Sprout, and Sprout always tried to do the same for him as well...

Though, on one particular journey, Cosmo got hurt on the leg due to Twisted Toodles because Sprout left him alone for a couple minutes, and Sprout wanted to make up for it...

"Sprout, what- what're you doing?!"

He yelled out, as Sprout stood outside of the elevator, and the time was slowly ticking down until the door would close...