This game has 6 endings, and which ending you get depends on Meltys' slut level and on whether you built up the castle again or not, with the exception of ending 6, which you specifically get during NG+ by kicking Esmeralda's ass during the prologue (which you're obviously not able to do normally).
Ending 1, the one I was talking about, is the Purity Ending, where you keep Meltys' Slut Level at 0. Do that and she gets together with the swordsman dude, gives up on being a kogal and we get to see her being cute and innocent with him where the most they do together is kiss. Now, the thing is, during this time Daliah disappears without a trace, and the two of them run into her at an inn during their adventures. It turns out that she completely lost her memories with the exception of her name, doesn't remember who Meltys even is and became the fuck-toy of a fat-ass pig-like inn-keeper. The game plays it off along the lines of "as long as she's happy yada yada"... but it doesn't really change the fact she basically suffered identity death, all while her mother lost a daughter etc.
Endings 2-4 are varying levels of sluttery, but the castle isn't constructed. I don't remember much about them since I didn't replay them this time around.
Ending 5 is the truly Happy Ending, where Meltys is a super slut, the castle is rebuilt, and you have several sub-endings in terms of who and where she fucks and whatnot.
So I was commenting on the fact that, unlike most other games out there, the Really Happy Ending is the most slutty of the lot, while the shittiest ending is the most Pure of the lot. Usually, the pure/virgin ending is the best ending for the characters in a lot of H-games. Which I admire in certain aspects. Wish more games did that. Reward the player and the characters for maximum sluttery.