zipper, trust me yoru just carefull, its natural, i've never caught it.
hard ons, are hidden just like normal by tucking it in yoru waist band and letting the t--shirt hang over
Chaffing, never had it, and i'm a 7.5 inch guy
The outline of your dick through your pants, i wear slim jeans (not tight but slim) and i've never had an issue
Baggy short when sitting down, ok, i wear jeans and only jeans so yeah, i dunno

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