The priest's story is what legit broke me and I had to pause from the chapter and just cry a little.
From her perspective, she meets the priest, Raphael, who is a a close friend of her ex-husband. She thinks OG Kanna had seduced him and then been like "lol jk" and broke his heart. And she thinks he hates her for it. Which is why she's really confused when he doesn't seem to hate her at all, but instead starts showing up every time she's in trouble to save the day. He never gives her a straight answer about why he's following her around and says he simply wants to be her servant and protect her.
When it comes time to start timeline jumping, she mentions she needs a place to stay safe, where "God" (her bio dad) can't find them. He takes her to basically a sacred garden in the temple that no one else can enter, and says he'll protect and watch over her body while her soul travels through time.
She does the timeline jumping and learns the full story. As children, she tried to run away from home once and ended up coming across Raphael dying in an alleyway. He has no desire to keep living and has learned he's basically meant to be a sacrifice for the scary God dude. She saves him, feeds him, and tell him to live for her. She tells him to become strong and someone she can depend on. And he swears that he will.
When she comes back to the original timeline, thinking things should be okay now, she can't see Raphael anywhere. But as she takes her first step forward, her foot knocks against a bone. A human bone, among a black priest's robe. She has a sinking feeling, and I remember feeling my own heart sink in dread. There's a note that says "Welcome back. I'm sorry I couldn't keep my promise to be here when you returned."
HE PROTECTED HER BODY ALL ALONE IN SOLITUDE IN THAT DAMN GARDEN, UNTIL HE DIED AND TURNED TO BONES. AND EVEN THEN, HIS DYING REGRET WAS THAT HE BROKE HIS PROMISE TO BE THERE WHEN SHE CAME BACK.
FL has a bit of a mental break down and cries over his bones and calls him an idiot and says she's not worth this level of loyalty and why didn't he just go out and live his life. Then she decides this won't do, and goes back to timeline jumping to fix this shitty end for Raphael.
In the end, FL has to sacrifice herself to stop the end of the world, and the "dad" was supposed to use his magic to save her. He ends up a little late, and finds Raphael dying and crying because he used his own lifeforce to extend hers long enough for the "dad" to arrive. He survives but is reverted to a child or something I can't remember (it's been a while since I read the novel)

I'll drop a huge spoiler here just so everyone can understand that FL had it easy out of all the Male Leads
Okay so I have read this novel and I have to say the synopsis was basically clickbait and I didn't sign up for the serious damage this story did to my heart.
This novel has really great ratings and I was willing to turn my brain off enough to move on from true ML being her dad. You guys. All I wanted was a lil revenge story. This thing was traumatizing. Every single character goes through some serious suffering and misery. But no one gets it worse than the “dad” and priest. I will probably think about how bad things went for the two of them for a long long time.
It’s really easy to just go “oh ew the Dad is the ML” but that really isn't the whole story. After I finished the novel, my main take was that out of all like 5 MLs, she deserves none of them. Least of all the "dad".
I’m not gonna bother with spoiler tags since it’s the only thing everyone is talking about here, but stop reading here if you don't want to know how this story really goes.
From the "dad's" perspective, all he did was meet a kinda crazy girl in jail that threatened him to break her out and then he fell in love. He meets FL in his youth a couple times and finally falls in love and asks her to just stay. She obv can’t (because time is moving at a crazy pace back in her og timeline and she fucking left someone waiting. I will cry over that shit forever). She tells him to wait for her and she’ll definitely return to him.
He ends up having to do a crazy amount of timeline jumping to find the one timeline where things don’t go to shit and the world didn't end. Which means he repeatedly sees the woman he fell in love with die. Along the way, the ML picks up some curse, and it’s slowly but surely destroying his health and his sanity. After multiple bad ends he realizes that he must have children with another woman and let them die for his magic to disperse correctly to save her and the world. That's still not enough. Then it turns out the only timeline where things go right is where he adopts the FL in her childhood. By the time FL remembers everything and tries to go to him, he’s in near constant pain, mostly lost his mind, and doesn’t want to be around her at all. He became cold and withdrawn when he saw the first glimpse in her that reminded him of the woman he loved. He got really excited and then was like Omg wtf am I doing this is a child. The curse gave him voices in his head that are mostly the people's he's had to kill and they all constantly shame him for having feelings for his "child" and "was this woman really worth all this pain and suffering"
I don't mind continuing and spoiling how bad all the other guys get it too if anyone is interested. The bottom line is that this whole novel is just Xtreme Suffering for everyone BUT the FL. She's like oh I had a bad childhood. Girl, the shit every single one of them goes through makes you sound like a whiny baby.