Actually you can lose in battles with NPC's, just not bosses. If you lose against enemies she'll be groped, her vag/anus will be stretched by hands but otherwise she wont be penetrated.
Contrary to what the game says you can beat that first mechanoid boss, same with the other bosses they're just much more difficult than the other bosses like say that kobold & the orc's later on. A pure route? Well don't walk into that alleyway in the lower slums, don't whore yourself, despite a "daily" limit on things you can beat the game pretty much day one without issues. Use the store, buy upgrades for your stats, alot of the "spells" are useless & you only need the strongest ones for healing against the final boss, get some for your witch so she survives but otherwise spend eplis on battle dolls and get stronger ones as you get more elpis/glim etc.
The impregnation mechanics were really underwhelming tbh; Ye she gets "impregnated" in the dungeon via sex but you gotta go back home for it to really occur. I wish he expanded it alot more like she'd get captured and tossed into a cage or little "room" that exists just to shackle you, some sex occurs then she gives birth quickly & you escape, this would be based on what captured you and the like on top bosses if they do the same thing have a unique animation/cg for it occuring as for capturing it coulda just been a simple reuse of what's there and just have a CG dependent on species that catches her oh well I guess.