Those cheats are for $5 patrons.
But he is you, so he kinda mimics your stats, including ones coming from your equipment... and winning by lust is generally easier, so go for a high END and defensive build, keep your atk low (so no sword equipped and such) and tease, heal when necessary, the bathhouse can also boost your HP and MP.
Or... lower the difficulty in your room, but it is an easy battle if understood.