I dont particularly think build is so important a thing in a game like this just due to the inherent RP-centricity of the whole thing.
If you want to try to keep the heroes 'sanctity, dignity, valiance, and class' intact going with the paladin at the start is a good choice because they start in chastity - though the low agility & perception could "bite you in the bussy"... metaphorically
If you wanted to roleplay something more like 'the hero is slowly corrupted along the way' the Warrior might be a good start because they start with the "Weak to Anal" debuff, which means buttplay is MUCH more effective on them - and with the high strength + mid endurance&agility they're far less likely to struggle in combat - plus you get extra skill points at the start which expands your combat/sexmat options further.
Personally on my first run I chose the Enchanter due to the high starting Charisma, and spec-ed first into perception then into strength and agility evenly which turned out to be a great start for me. Able to do virtually any talking/schmoozing I wanted - but without combat being something I needed to avoid outright.
After the class select you can choose skills - personally i think you should refrain from investing skill points in sex skills unless you have really low strength and plan on trying to seduce everything. Even as the Enchanter on my first run (highest charisma - strongest sex... obviously) I struggled to really understand what, why, or how to use those skills. Combat is much easier to get acquainted to just because you start encounters in a combat stance already 9/10 times.
As for actually picking those skills out - I would just read. See what sounds useful even if you dont totally get the mechanics from having yet to see it. I think getting Blitz attack and/or Reel Back from the offensive stance list is a great first investment, Parry from Defensive stance is nearly a must to me, but Center is also extremely useful - and in Balanced stance I grab Slide if im able to.
Magic is pretty self-explanatory so i wont get into that.
Perks are something I'd say is entirely up to you based on your other decisions so far - but if you plan to come out the gates sluttin' then erotic, cum drinker, and flexible jaw are all pretty good picks. If you plan to avoid intimacy as long as possible, then Stealthy, Sureveyor, and Forager are all worthwhile choices. The stat gain Perk are also good imo.
The last screen is character customization, WHICH MATTERS. The different races have different starting boons/blights baked into them. Personally i like orcblood - but the increased hunger can become brutal. If you want to play a masculine-leaning character - then lips should be either thin or full - Butt should be as small as you're willing to have it be, Chest should be flat, im not sure that f(ph)enis size actually matters, but I could be wrong easily - and therefore for a manlier enby id pick average and then set Syle to maximum: Masculine. For a more femme character basically do the opposite of what I just wrote,
hope this hit on anything you may have been looking to figure out - especially if youre not too familiar with this style RPG games. if you have any question please feel free to ask