It's chapters like this that have the subtle hints that it's gonna go the incest route but we don't have the tags makes me wonder if the axe looming in like 10 chapters meant they never really got to any of the romance part. It's kind of odd cause the Synopsis clearly states sometimes lovers refering to the siblings.
Really though theres been no romance at all in a romcom which I find funny lol, most we get is Momo's friend liking Ao.