91 Days, Hakata Tonkotsu Ramens Recommendations
Both anime include revenge as a plot point. For Hakata Tonkotsu Ramens, it's relatively short since the series is pretty episodic. If you want to see a whole story of revenge, then 91 Days is the anime you want to watch. Also, both give off a similar vibe. They take place in different time periods, but both have a 1920's-1940's feel with the mafia (from 91 Days) and the hitmen (from Hakata Tonkotsu Ramens).