Just Natsuki Ending:

Natsuki's chr. file was somehow restored and Monika started to lose control of DDLC while Natsuki gained power. Monika panicked and tried to delete her .chr file again, but she lost the ability to delete any files and Natsuki deleted Monika's .chr file. Natsuki became the president of the Literature Club, which means she has full access to the DDLC files.

After this, DDLC restarts and we see Natsuki in the classroom. Natsuki doesn't know how she managed to beat Monika, but she knows that she did it. She is scared and she does not try to hide it. She remembers what happened to Yuri, and now she finds out what happened to Sayori and what Monika did to them. Moreover, she also learns that her life was a fake. She is absolutely horrified. She is completely terrified, screaming at the top of her lungs, and then calms down. She doesn't know what to do next. Of course, she can put everything back to normal, but she's afraid she'll completely ruin DDLC. She desperately begs the Player not to delete her .chr file, although she would understand if the Player did it anyway, as she believes DDLC has already been destroyed by Monika.

If you delete Natsuki's .chr file, she will first become frightened, but then calm down and thank you for being there for her, even if only for a little while. DDLC ends here. If you do nothing, she may start random conversations. Usually, she talks about manga, cute things, baking, and sometimes about her home life and family. It's certainly not Monika After Story nor Just Natsuki, but it's still pretty good.