Well, the ones in rock mostly seem to be holes, or depictions of holes...

That leads one to conjecture, based on The Law of Fives, that the poster may be obsessed with holes.

Now it has been assumed so far that the poster is male, so now we have to decide whether he is obsessed with male holes of female holes, or just his own arse hole...

... or is it just too much contemplation of his own navel - you know they could look like that...