Not to defend Sakura, it is in her nature to be submissive but she was emotionally vulnerable, she does have a trauma for cheating, I think a key thing in this story is that all of Sakura's blatant cheating are linked to Shinobu.Who cares if its out of pleasure or love. What does that change?
Sakura is still a cheater who betrayed someone who did everything for her. She still never attempted communication and opens her legs from getting touched. She obviously didn't trust Shinobu, hence cheating on him. Shes still selfish and ghosted Shinobu not caring about how he felt. She still did things significantly worse than kissing someone, like sucking dick, and hid it from Shinobu. Also, all that dick sucking and getting lingered didn't seem to mentally bother her at all earlier in the story.
What the hell does it matter if she's sleeping with fuckboi for pleasure or love? Shinobu winding up with Sakura would be unbelievably unfair for Shinobu.
She went as far as she did with the director because the director was able to make her think it would improve her relationship with Shinobu, playboy took advantage of emotionally because she was upset about Shinobu, she should be doing more, she should be thinking more clearly.
Again, not defending her but that's just how she is, I'll be ready to crucify her if these next few chapters show her being happy with playboy and slandering Shinobu, if she starts acting lovey-dovey with playboy, being the one to start sex with him, kissing him herself and getting on top of him then yeah, she's got no hope left.
But look how these last few chapters have played out, we're not seeing her thoughts, we've just seen playboy and blondie take advantage of her while she's emotionally weak and this is being done on purpose, until we see Sakura's POV, I'm willing to give her the benefit of the doubt, to be clear, I'm not rooting for her to get back with Shinobu, that ship has sailed, i just want her to acknowledge what has happened clearly.
But of course, regardless of whether i want it or not, author can and will force Sakura and Shinobu back together at anytime.