Dave and Terezi do a shitty sidequest and experience the Dark Nak of their Soul.

“Maybe we could just – not talk. Until the effect wears off.” “It shouldn’t be that hard,” Lan Xichen said encouragingly. “Given that it’s us.” “What’s that supposed to mean?” Nie Mingjue asked suspiciously. “Well, it’s not like the three of us ever talk anymore,” he said, and then slapped his hand over his mouth. Jin Guangyao could not wait for the truth-compelling effects of the smoke to wear off.

What sort of servitude ceremony was this? — In which Shang Qinghua didn't leave.