Ok, so, the version I played was the 1.1 Translator version, uncensored and all that jazz... and I don't remember needing any save scumming to reach the True Ending. Hell, Kana can be fucked and even impregnated by Lawrence, and that doesn't actually prevent you from reaching the True Ending. The True Ending isn't the "No NTR ending", though you can certainly make it that way. It's the ending where the MC finds out all the truth and accepts everything about Kana, good and bad, and solves the issues in town before L can fully corrupt Kana. Additionally, depending on how you handle things MC can reach the point where they confront L about their blackmail of Kana, which causes any further NTR events to stop.
Now, yes, it takes a bit more effort if you want Kana to never get fucked by L. You probably can't avoid at least some breast groping during the day-time parts because it'll take a while until you get some decent cards and catalysts, at least, if you're aiming for this ending on the very first playthrough, but it's not difficult if you pay attention to the game's systems. Stopping the night events is easy too, given that Kana always gives a 30 minute notice to the MC about her location...
More importantly, you don't need to wait until the notice to find her.
It seems like a lot of people miss this, but Kana's location on the map changes on the dot when the hour changes, and when that happens you can find her before she calls. On top of that, the NPCs in each part of the city map give hints about her location that make it easier to find her. If she's in the center map for example, and at the maid-cafe working part-time, then the NPC there will comment about Kana in her work uniform being cute or something like that, and you can go in to check on her. If she's at the bar, the comment changes. So on and so form.
Quite frankly, one of my complaints was and still is that it's TOO easy to cock-block L once you figure out how the game works. In the day-time you can just make Kana invincible with some effort, on top of making things easier for her in general via combat + controlling her route. In the night-time she's too easy to find even without the text messages and/or calls.
For me, I'd have honestly added more night stuff for MC to do, so you genuinely have reasons to choose between protecting Kana and doing something else. Particularly if it's stuff that can only be done on weekdays, so you can't always take advantage of L going away for the weekend the way you can for night exorcisms. The other thing I'd have done would have been to tweak the spells and stuff a little so there's more viable combinations and whatnot, since the combat does get monotonous after a while outside of the boss fights.
