Understandable.
Although Gwen's yandere mode isn't as hardcore as some "yandere connoseurs" claim.
I mean, she won't kill anyone in the harem and by the nature of the power we used on her she can't really do anything to you either.
Unless you let her do that.
But still, I personally just bang her every now and then to keep her from getting stabby.
She's the character I have most sexual interactions with.
And frankly, she isn't on my top 5 (excluding side girls).