I do remember Kate's Test, and thinking back that was similar and did come first. I think it's the layout that really called evoked Sol Rui in my mind since I played it more recently. The lust bar, corruption heart, and 5 heart life bar on the side before you get a soft game over.
Not trying to call you out or anything, creators grab good ideas where they find them, then twist them to fit their vision all the time. The layout just screamed Sol Rui to me, and as a fellow fan, I just wanted to say you had good taste.
I like what I see so far in this. I look forward to buying it when it releases.