>>81776600 (OP)im a switch, so this will come in pairs:
Sub appeal:
the concept of handing over control of your life to someone else that you genuinely can trust to not hurt you is alluring. In my case, it's likely from being parentified as a kid and seeking that feeling since I never got it.
pet play is also a form of "soft" BDSM, in that it is mostly centric on the power dynamics and trust and NOT necessarily on pain. being doted on, caressed, and desired for who you are and not what you provide, at least temporarily, is highly alluring to broken people like me who never got attention.
overall, its a desire to both be helpless to another AND treated right in that helplessness, it's a form of sexual trust-fall in that way.
dom appeal:
giving care to another person and seeing them in a very vulnerable state is very appealing when you genuinely love someone for who they are and think they're precious and worthy of protection. being able to give someone a safe space to express themselves truely as they are, without regard to social norms or desire for life goals and independence is beautiful. it allows them to act very instinctually and true to what they are, without all the layers that they're forced to put on to just function in reality.
now, of course, its still sexually appealing. being able to press the buttons of someone and see them squirm, whine, and otherwise shut down or make cute noises or do cute things is adorable. when they're that vulnerable, they have no reason to protect themselves by acting tough. Since they trust you, that's not distressing since you can accept them for what they are.
pet play subs are especially adorable when they're sweet hearts or meek at their core, it lets them express that side of themselves in a safe and controlled way. pet play is just a language through which that safe spot can be carved out and the surrender to another can be expressed, there's many other types and ways of doing this as well.