Don't want to lose my manhood

OHHH. I GOT IT NOW xD
He was actually using the tissues to wipe away his tears after all those heart-breaking Disney/Pixar movie moments. Unable to admit this to his mom, however, presumably out of embarrassment, he lies and admits he had indeed done the fapping business.

Now that just doesn't make sense. How can you lie and admit something when admitting means to confess to the truth?