Jukai is horrified by what Hyakkimaru has become. While Hyakkimaru sees his quest to regain his body as a righteous path, Jukai sees a man losing his soul to bloodlust and obsession. This creates a philosophical clash:
The meeting is far from the happy homecoming one might expect. Hyakkimaru’s calling Jukai "Mama" (Mother) is a poignant moment that highlights his childlike attachment to the man who gave him a second chance at life. The Weight of Humanity Dororo Episode 17
Critics and fans often point to the visual representation of souls in this episode. Hyakkimaru’s soul, once pure white, has begun to show flickers of red—a sign of the human lives he has taken. Jukai is horrified by what Hyakkimaru has become