Ariadne and Bob is a 2+ player roleplaying game about a know-it-all and her trusty sidekick going on adventures and getting in trouble. Ariadne can be condescending at times, but her ego is not entirely undeserved. Bob is Ariadne's long-suffering partner. The Pinky to her Brain, Morty to her Rick, the Sherman to her Peabody, etc.
This game is an absolute blast to play, and it requires no prep at all. My group has been playing it whenever we have an absence from our main game, and it's perfect. We can bust it out on short notice, it works great with low player counts, and it's built for 1-shots so we can get in a complete story in one session.
And for fans of Strike!, I am also throwing in The Ogre, a pair of classes by Gabriel Butche. As The Ogre, you and a friend control two characters in one body. This is one of the most unique tactical combat classes in any RPG, and it's very fun to play