>>281772965
Denji refused because no sex was involved in killing the children. No temptation, no deal. Had Aging turned into a sexy woman and offered him sex, Denji would have killed every last child. That's a fact.
How do we know this? Because Fujimoto is strategically revisiting every single situation Denji was in, and painting the outcome in a different light based on whether Denji receives help and/or reward of sex. He revisited the Falling devil scenario only 5 chapters ago, but this time Denji received no external help from Yoshida, Asa, Fakesaw and Nayuta. How did Denji fair again? He jobbed instantly to Falling. No help, no win. Same will continue to happen, Denji will once again be tempted to kill children, but this time he'll be promised sex as a reward, and Yoshida won't be there to bail him out. Guess what he'll do?