A Japanese coworker whom I'm also very close friends with in real life has asked me if I could be a sperm donor so that she can have a child. She's already mid-30s and she feels like her biological clock is ticking but she hasn't met the right guy yet. She's very intelligent and career oriented and makes a good salary, so she could easily support a child on her own. I told her that I would be happy to help her out if she's willing to take on that responsibility by herself, and she enthusiastically agreed.
A few days later, she messaged me and asked if I would be willing to put my name on the koseki as the biological father. She said that the koseki in Japan is a big deal, and there is some stigma attached to children who do not have a father registered on their koseki. My understanding (based on a quick Google search) is that acknowledging paternity on the koseki would legally obligate me to support the child, and that I would be subject to child support payments should it ever go to court. I'm not saying she would do this, and I trust her as a friend, but having a child changes people and their circumstances so I'm hesitating.
Is there any way that I could acknowledge paternity on a koseki without being legally bound to financially support the child? Or is that simply not an option according to Japanese law?
by Constant-Row-4692