GilliamYaeger
M'crazy.
It's a visual novel, not an anime unfortunately. And I'm honestly not sure if you can adapt it to anime, since it's one of those stories that relies heavily on the medium - in this case the whole story is an eternally repeating four day time loop, through which Shirou (and the player) stumbles blindly in search of a way out, with everything between the serious bits (both involving Shirou and the mysterious newcomers Bazett and her Servant Avenger) being filled in with fun but mindless slice of life segments that treat all three mutually exclusive stories from the original (those being Fate, Unlimited Blade Works and Heaven's Feel) as canon with everybody being inexplicably alive and happy.Ooh, I'll have to check that out after the series as well, then!
There's always Carnival Phantasm though, which is vaguely similar if a lot sillier.