Does anyone know of other games with this style of complex dungeon crawling gameplay but that's an actual game (not even +18)? I love this style of games, but the bondage punishes are just incredibly dull
Well, there's Pixel Dungeon and its many, many derivatives, the biggest and most popular being Shattered PD. It's a delightful little game that has a surprising amount of depth for its simple interface and a lot of replay value. The developer is very active when it comes to balancing and adding new content, having worked on the game for close to a decade (might be more, not sure). You can play it on both PC and mobile, though I definitely prefer the mobile version.
There's also Caves of Qud, but I found it a bit overwhelming with the amount of mechanics it throws at you, though if you're looking for depth, you'll find no shortage of it there. Bit on the expensive side though (30 quid) and the graphics might be not to your liking.