Review of School Days
Okay so without spoilers? This anime is pretty slow however becomes aggressively anger inducing once the build up happens. Taking things for granted is another huge theme here. It points out some very important life lessons when it comes down to messing with other people's feelings like what happens when you ignore those you once said are important, disowning the problems you created and blaming others for them, and refusing to take accountability for your actions. It won't only ruin the lives of those around you but it will eventually come to ruin yours as well. Treat people how you would like to be treated cannotbe stated enough here. Your friends. Your family. Your relationships are not playthings for your personal gain. Period.
The coward and infantile like mind of an individual who thinks the world revolve around their feelings and only their feelings will never end well. Narcissism rears it's volatile head in the most awful of ways and it didn't stop at a love interest and intimate relationships. It followed right on through to general friendships and close friendships as well.
This anime reveals that dishonesty doesn't actually grant you any favors. You may get away with your secrets and lies for a while but it'll always catch up to you be it sooner or later.
Given how this anime played out? I honestly approve of how it ended as well.