Well, in light novels, 'Punching Bag MC' could be a character type. They might be the one that all the bad things seem to happen to. Maybe they have a weak personality at the start and others take advantage of them. It's a common trope to create drama and development in the story as the MC gradually overcomes these situations.
Sure. 'Orange' is a light novel where the main character has regrets and tries to change the past. In this process, she kind of acts like a 'punching bag' as she faces the difficulties of trying to change the fates of her friends. Also, 'Your Lie in April' has elements of this. Kousei, the main character, has his own traumas and is sort of a 'punching bag' to his own negative thoughts and the challenges he faces in the music world.
Blade Fangs was a Japanese manga created by Itagaki Keisuke. There were four works in total, namely Grappler Blade Fangs, Fanma Blade Fangs, Blade Fangs Path, and Blade Fangs Path 2. The theme of this manga was hand-to-hand combat, and it told the story of the young Blade Fang fighting with strong enemies in various underground arena competitions. The characters in the Blade Fangs series had distinct personalities, compact storylines, and unique styles. This series of comics was well-known in China and was welcomed and loved. The animated version of Blade Fangs also had two seasons and could be watched online. As for the viewing order of Blade Fangs, they could be viewed in the order of Blade Fangs 1, Blade Fangs 2, Fanma Blade Fangs, Blade Fangs Path, and Blade Fangs Path 2.