Well, it actually happens with all the girls I tried to go to bed with, except Etsuko (haven't tried with Ryia): you ask any of those girls to come to your bed and then Anabelle's scene always plays instead.

With Etsuko everything works properly: her bed scene plays correctly, you can propose to her and the ending plays to the end. However, I must say that playing that route I stumbled upon something funny: after proposing to Etsuko but before the wedding, I asked Astrid to come to bed; as expected, Anabelle's bed scene played instead, but when it finished... Ryia's scene began to play. When that one finished, Hyacinth's scene was shown. And finally after that, Astrid's scene (the one girl I actually invited) appeared. After that scene ended, the game continued as normal.

Apart from all of that, I've also found the following bugs:

• Inviting Hyacinth to the ruins makes Ryia appear instead.
• Inviting Clarimond to the Auroras doesn't play any scene at all.