The God of Destruction, Lord Beerus, is easily one of the most ruthless beings in the Dragon Ball universe, which is a given based on his god-level position in the cosmos. However, there is one Dragon Ball fighter introduced long before Beerus who proved to be way more ruthless than even the God of Destruction himself–at least, in one aspect of their similar quirks.
Lord Beerus made his first appearance in Dragon Ball Super chapter 1 by Akira Toriyama and Toyotarou. In the chapter, Lord Beerus destroys a whole planet because he didn’t like the cuisine on that world. Soon after his explosive debut, Beerus travels to Earth seeking out the legendary Super Saiyan God as he wished to fight this being to measure its supposedly immeasurably strength. When he gets to Earth, Beerus doesn’t initially find a Super Saiyan God, but what he does find is food the likes of which he had never tasted before. Since then, Beerus has made an effort to go to Earth every once in a while to have a feast fit for a god, and the chefs in charge of feeding him always make sure he is satisfied for fear of having the entire planet blown up if he is not–which is a very real possibility.
In Dragon Ball chapter 139 by Akira Toriyama, Goku is trying to track down the villain who killed Krillin a few chapters before, and he is doing so by following the signal made by the Dragon Ball the assassin stole from Krillin after the Z Fighter was killed. However, before enacting his vengeance upon Krillin’s killer, Goku happens upon a man named Yajirobe who was hanging out in the woods by himself looking for something to eat after Goku thoughtlessly ate the giant fish he was cooking for himself. Then, suddenly, a minion of the villainous King Piccolo named Cymbal lands before the two warriors as he was tasked by Piccolo to find the Dragon Balls and bring them to him. Since this villain was threatening both Goku and Yajirobe’s lives, Yajirobe took it upon himself to fight Cymbal and he is successful in killing him by way of a swift slice with his sword. Afterward, Yajirobe eats Cymbal which is decidedly disturbing especially due to the fact that not even the food-crazy Goku would have a portion of their former foe.
Cymbal was a dragon-like ‘demon’ born from an egg laid by Piccolo–a being of mysterious origin who was believed to be the king of demons at that time. Basically, Cymbal was a totally foreign creature who could very well have been toxic upon being ingested, but Yajirobe didn’t give it even a single thought and ate him anyway. Not only could Cymbal’s meat have been deadly, but the moral ground on which Yajirobe was standing was questionable at best. Cymbal was a sentient creature and a worthy adversary, so to eat him moments after killing him is, for lack of a better term, just wrong.
While Beerus is food-crazy, he has never eaten one of his opponents (as far as fans know) and he certainly has never tried to start fights with the intention of killing an adversary to then eat them immediately afterward. That isn’t to say Beerus won’t kill an entire planet just because he doesn’t like their food, because he absolutely would and has done that, but he wouldn’t take his quest for a good meal as far as Yajirobe did in this chapter. Yajirobe doesn’t have any hang-ups about killing and eating his opponents whatsoever–proving that, when it comes to food and what they will do to get their fill, Yajirobe is way more ruthless than even Dragon Ball’s Lord Beerus.