The characters were literally retarded. The childhood friend fucked around like a whore and the cuck guy was ok with it. He even jerked off to her getting fucked. But our MC got to fuck a couple of girls who suddenly feel in love with him so we don't feel too bad for him. But it was still NTR. And shitty at that.
If my childhood friend who I loved acted like this I would leave her forever.
In the end they got a 'happy' ending.