I don't really like it. I think it's mostly because I can't take religion lightly, because autism or something. I can't change that so this will be very biased.

First two phrases: don't describe what category you fall in, talk about how you feel. Especially if you're the kind of person that write about someone that is the kind of person that says "Well, actually I'm not an atheist, I feel more like an agnostic". It's like you're dying to talk about someone but are too afraid to talk about it. If this is self-censorship because you think people won't like it, two things. First: take a look at where you are, an objective look. Even if you do something cringe people will "forget" by the next post because this is an anonymous imageboard. Second: please don't rob people of the chance of reading your stuff and enjoying it, and please don't rob yourself from the chance of writing about it and sharing it. If I'm wrong, feel free to ignore everything.

"Now, neither of you regretted it and nothing bad happened afterwards, but considering that Nene is an angel, the fact that a mere man like you had sex with her could be considered the ultimate blasphemy. So you both felt like confessing, just to be safe." I'm not Christian/Catholic/whatever myself so this may be me getting angry on other people's behalf when they themselves have no issues, but I don't think confession is something you should do when you feel like you've done nothing wrong but just want to be safe. It's like you believe God is powerful enough to grant you eternal life, and choose whether you end up in paradise or in hell, but he's too stupid to see through you. My knowledge and understanding of religion mostly comes from sleepless night on wikipedia, but the way I see it is that people will be judged individually and you can't know the result in advance precisely to avoid taking a checkbox approach to religion and heaven. Saving thousands of people doesn't give you the right to hit someone for no reasons, and a life of crime doesn't mean stop you from heaven. On a more pragmatic level, this allows people that have lived a life of sin to turn over a new leaf at any point which is beneficial for society, and it ensures that there are still things in place to prevent people with high status/power to do everything they want.

Same thing with "with to repent", I don't feel like any of the characters actually want to repent. If you want to give a feeling that they actually want to, you would need to spend a bit more time, for exemple describing how they both enjoyed it but are both more and more wracked by guilt, and feel like they have to confess, but don't want the other to think that they did a bad thing so they go to confess in "secret" but at the same time and they find themselves. I'll come back to this later.

After that God appears, forgives them because it was fun, and they continue to go together. I think there's a big issue here: it's religion, but they need God to appear, tell them something, it's not enough and they insist to know the reasons, and after hearing them they're okay. Forget faith, they don't even trust God when he appears and tells them something. One of the most important part of religion is faith. Faith is being okay with not knowing. If I had to explain what I think faith is in plain words, it would be "trust the plan". There is a reason or things, you can't understand why because you're human and humans can't understand God, and since you can't understand him rationally and thus trust him, you need faith to bridge that gap. If you need a confirmation, it's not faith. You can think whatever you want about this, but that's how it works.

Going back to my alternative version: they both find themselves at the place where they confess. They go through the process, not talking to each other, leaving the church in silence. Cut in to them in bed, after their honeymoon, talking about how lucky they feel that they both went to confess at the church at the same time. That it was almost like an act of God. That they see things the same way, which reconforted them since they were worried sick that they were going to drift away. That this gave them the strength to stay chaste until tonight, because they knew that there would be a payoff at the end (modulo life events), and that they didn't have to try to take every bit of pleasure along the way because it wasn't going to vanish tomorrow (ie it's easier to not fuck around if you know you'll have regular sex in a while (and it's easier to live a moral life if you believe that you'll end up in paradise)).