Theres one blanked out option that i cant find the trigger for in the love route. Its the option to say "its not my choice to make" or something to that effect when talking to the fat coffee shop guy. Its in reference to the fat guy wanting to date Yasuka in return for him helping with the debt. If there is NTR at some point in the future, im betting thats the trigger for it. There were one or two other blanked options from what i recall, but even though i cant remember specifically what they are, it seemed like unfinished content rather than an NTR trigger.
Having now finished the large majority of content now, i do stand by my original comment just a few after you made the one im quoting. This doesnt need to be a "game", in its current format it should just be a VN with route choices, the amount of clicking on destinations is pointless when theres no actual gameplay. I do have some thoughts on the choices though.