Even though Chandra and Abby are obviously not the pinnacle of prudence and reasonableness
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I hope that the way we will get to a threesome with them won't be in the spirit of Adam Sandler's or Seth Rogen's scripts justified by some childish and hilarious reasons.
The circuit of those comics looks as follows:
Protagonist comes over to the psychologist (Carli) and briefly discusses some crap with her
It is turning into a prelude to sex
Rough sex
They are not bad and might be a must have for Carli fans. But they actually do not contribute anything to the stories and the characters background behind DA and CoBD. As for me, I would easily do without them and trade them for a higher renders number and longer more meaningful dialogues for forthcoming chapters of CoBD itself without hesitation.
But it's me with my preference for a story-driven experience without unjustified gratuitous sex for the sake of sex. For everyone it depends on what you look for.