Because spermatozoa cause itching from the inside
Therefore the more sperm they have in their testes, due to their above-average manliness (naturally), the worse the itch becomes, and hence the greater compulsion to scratch. Trufax.
(LongJohnBaldry, Fri 15 Jul 2011, 12:29, 2 replies, latest was 15 years ago)

so the sperms tickle your insides?

( Citizen Cavy Admires your passion for conformity, Fri 15 Jul 2011, 12:31, Reply)

Don't they tickle yours?

(LongJohnBaldry, Fri 15 Jul 2011, 12:31, Reply)

no
they are busy getting their mattocks out to clamber up the plumbing
( Citizen Cavy Admires your passion for conformity, Fri 15 Jul 2011, 12:33, Reply)

Maybe it's just mine, then - they're visible to the naked eye.
And feathery.
(LongJohnBaldry, Fri 15 Jul 2011, 12:34, Reply)

they aren't sperms
they're axolotls
( Citizen Cavy Admires your passion for conformity, Fri 15 Jul 2011, 12:35, Reply)

What the hell are axolotls doing in my testes?
Also does this mean that a stem cell research centre would pay for my cock custard?
(LongJohnBaldry, Fri 15 Jul 2011, 12:36, Reply)

I'm just going to imply that
you put them there yourself

I'm off to be pretentious
( Citizen Cavy Admires your passion for conformity, Fri 15 Jul 2011, 12:37, Reply)

Have fun.
In an ironic, post-modern way that juxtaposes the isolation of ...oh fuck it, I can't be arsed. See you later.
(LongJohnBaldry, Fri 15 Jul 2011, 12:38, Reply)

So most of you
just scratch to look manly, don't you?
(Aberracion Life's getting very complicated, but a lot of fun., Fri 15 Jul 2011, 12:40, Reply)