Susuka's mom? the person he refers to as "that woman"? If so, then yes. She's his bio-mother who was married to his dad. she had an affair and left both of them to be with her lover. Now years later they're trying to get him to help out their kid and also dropping the bomb that his dad isn't even his bio dad and that he was the son of that lover she cheated with. so if true, Susuka is his 100% blood sister, which they've known all along, but are only just now reaching out to him because he could be a good donor match for her illness.
Thats.... super wild and unfortunate. She left her own son with his father (whom is actually his step dad unaware but she knew) didn't even reach back out at all since she was happy but now that MC actually sister need a donor they ask him.. super fucked up in my opinion, I see why MC is crashing out on his dad
yeah, pretty understandable. I can understand not wanting the little girl to suffer while also wanting to jab a big ol' middle finger at the parents.
I assumed the MC was related to the mom but no. I'm so lost.