#his child would be fucked up mentally because of sj’s own moral compass

[scumvillainess]

to me, shen jiu doesn’t seem like the type of person who would have a child because he wants to be a parent or because he likes kids (we all know from canon that he absolutely cannot stand children), it would be because he either wants to prove a point through becoming a parent or because he wants someone to love him unconditionally because children are naturally inclined to love their parents unconditionally from birth.

I absolutely don't think Shen Jiu should ever be a parent, but I think he would be a bad parent in really interesting ways, even when circumstances are otherwise right for him to love his child (there are many ways for circumstances to Not be right, but we will not be getting into those today). There's a lot of ways for that to play out, but imo, these are his main flaws that would affect his parenting:

SJ is not good at regulating his emotions; in canon, as an adult, he seems to repress his "weak" emotions and let anger and resentment simmer until he blows up. There's a lot of reasons why emotional regulation is an important parenting skill, but the main ones are that children often pick up whatever behaviors their parents model, and SJ would likely pass his bad relationship with his emotions on to his child, and perhaps more importantly, that poor emotional regulation makes parents more likely to lose their temper with their children and treat them in cruel or otherwise age-inappropriate ways that they wouldn't normally.

SJ is bad at taking care of himself, particularly his emotional needs. There's several different possible outcomes of that, but I think the main considerations are that a man who is falling apart at the seams or rocketing towards is own self destruction will Not, generally, be very well equip to take proper care of another child. The second factor there is that an irresponsible parent often creates an adulitifed child as the child tries to either take care of the person they love, or mitigate the risk of their parent's poor moods.

SJ hates himself. Aside from the afore mentioned problem with modeling behaviors, if SJ too much of himself in his child could cause him to project that self hatred onto them as he does with Binghe in canon. 

SJ has [Qi-ge induced] abandonment issues, and in any situation where his relationship with YQY isn't fully resolved/mended, he is sure as hell going to be putting those issues on this little creature who has no choice but to love him/who can't leave him, at least for now. SJ doesn't trust anyone to really love him, which means he'll either preemptively place emotional distance between himself and his child in anticipation of them coming to hate him, or he'll desperately cling to the child's naive affection, certain its a limited resource that he has to preserve by force.

Anyways. We've see the range of how SJ treats children that aren't his with LBH and NYY, and I think that with SJ's own child, they'd likely experience that whole range, first in line for both his love and anger, stuck standing to close to a fire that both warms and burns.