Part 6/10:
After a conflict in a church-turned-parasite hideout, Kang-Woo and Su-in's paths converge, with the revelation that Su-in is cohabitating her body with a parasite named Mr. Heidi. Unlike others, this parasite had a lingering sense of loyalty and energy preservation, lending a bit of humanity to its sinister nature. Their lives intertwine further when the parasite assures Kang-Woo that together, they can repel the true threat that the predominant parasitic species poses to humanity.