Hi, this is what it says according to the FAQ guide:
- Emma [ Seduce her but DO NOT share with Mario, after this you will be able to invite her while she’s at the terrace or the library at Mario’s villa ]
- Katarina [ Fully seduce her at the terrace until she is meowing for you and tells you Mario doesn’t matter, then you can invite her either at the terrace or the library at Mario’s villa ]