Hi! Ocean, the Dev of SG and WIAB, is not a fan of harem games, the max is a "throuple" relationship and you have to consciously play for that, else you have a normal couple relationship with one of the possible LIs.
Likewise the sharing and/or NTR paths for the various girls (not all have one or both) have to be consciously decided to follow, you cannot reach them by pure chance. (Well, maybe if you click the choices totally random as well, but that would be roulette

)
If such events happen, it will not blindside you and you will be responsible for it, will not happen just so. so you can rest peacefully on this.
My favourite girls in WIAB are in no special order: Ayua, Bella, Nadia and Nami