Man, as a Nat x Darrel fan in this game, I would really like for this to happen.
And perhaps to conclude the Darrel route, maybe include a scenario in which the couple finally agrees to make Darrel impregnate Nat (in her non-safe, ovulating days) which would lead to a non-stop intense and spicy baby-making sex all night long while Ethan is in another room, hearing them finally conceiving a child, and in the morning she enters the room and sees Nat exhausted from sex and her p*ssy dripping with so much cum which is the result for being creampied multiple times while Darrel hugs her in their sleep. And panels later, which would take place months later, Nat is finally pregnant which similarly resembles the vision that Ethan had when Darrel first creampied Nat during their cuckold session in the hotel.
For the NTR route (particularly the Ethan oblivious route): Its similar but without Ethan knowing like when Nat gets impregnated by Darrel, they would just trick Ethan that the baby is theirs and I would leave it up to the dev to conclude when Nat gives birth to their "child" lol