Ch 20 start with Akira healing 3 elves (former demon lord's subordinates) and tell the current gen 'chef' goblin to cook food for 2 patients.
Then when he came back one of them (middle sis) is up and beg for him to 'order' her sisters to live.
Basically, elves are of the never-age type of immortal, but ironically over time they tend to lose interest in living and just slowly starve to death.
Right now these 3 sisters are the last of the elves, and the previous demon lord found them, use his Law of the Jungle skill and order them to live.
So the girl ask Akira to do the same to her sisters so they will survive.
Akira accepts. Right then the other 2 girls wake up.
So Akira tell the middle sis to help those two up.
THEN CHUCK THE ROCK GLAIVES (not rock grave :v) AT THEM
since, reminder, the condition to activate LotJ is to 'defeat' the opponent first.
The girls are fine and Akira order them to live as planned.
Then while Kuro is feeding the girls the prepared meal, Akira sneak away to cough up blood.
Because obviously using attack on weakened girls would be lethal, he used "Substitute" skill so that he took all the damage instead.
Karen show up and just say "that's just like you"
The middle sis elf then came over and swore her allegiance to him (which he mentally tsukkomi how even though he didn't use LotJ on her, she's still super loya.
Ch 21 can be summarized as : sexy elf is sexy with new clothes, Akira try his best to hide the horny, and Karen get jelly and show up in a dress (ch 15 redux, now without attempt assassination?)