Real worst possible way to look at it is that anon is only doing the “funcle” things (going out places and buying nice shit) for the kid. If that relationship goes somewhere he might be the person who just financially supports the kid and SO. However I’d imagine any serious relationship (that is projected to be a long term commitment like marriage), would include blending households and sharing some of the responsibilities of child rearing beyond being a piggy-bank.

If so, Being a parent will require you to do the not so fun things:

• Getting zero sleep sometimes because your kid is sick (knowing you will catch what they have the moment they get over their cold)
• Having to actually parent while being told by your kid you are the worst thing in their life (compounds it even more that anon is a step-parent who has to juggle not overstepping his boundaries).
• Spending a lot of time (hours on end) making sure your child is receiving the emotional, social and physical needs they require and feeling like you always come short in some departments.
• Doing all the above while trying to juggle the responsibilities of work and life as an adult with little to no relief because you are the adult in this situation.