dex can increase ALL types of dmg, even damage from sexual attacks. you won't need dex in the early game for a slut build, but clearing lvl 3 and beyond without dex will be a pain in the ass. so, try to invest in it early. tho the priority is mind and willpower.
for unarmed, well I haven't seen anyone trying to make an unarmed build, but dex is still useful there
No? You are mistaken, STR is what increases all PHYSICAL damage as well as increasing CRIT RATE and specifically boosts Impact type of attack as well as giving you physical defense
DEX increases CRIT DAMAGE and boosts Slash type attacks but most importantly it allows you to actually land hits, it does not increase ALL types of damage
DEX also specifically boosts sexual attacks as stated in the sexual skills' descriptions, all of which say that the skill damage is dependant on Sexual Skill Level and Dexterity
But yes, Dexterity is useful in all builds due to its ability to make you land hits instead of hoping for the lucky 10 billion damage once in a blue moon, unless you are doing a counter build since counters don't miss I think
Remember to talk to the guards to learn what stat influences what
