My second (terrible) attempt at doing a translation of a comic I myself would like to seen in English.

That's some serious NTR'ing. Not only gets her boyfriend stolen from her but her body as well.

Base +6, Dark Mac +12, Remeark +6, Nausea +7, viniccius36 +4, somethingyousee -6, m42a +16, budgieboi +6, Serena Lea +6, Starwind08 +10, Bravelance +6, IncognitoMaud +6, Ildzmer +7, and 5 more...

I feel sorry for the girl, but really -- when a weird-looking guy you've never met before calls out to you and asks you to drink some "medicine", you don't drink it... you RUN AWAY.

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At times like this the only way the protagonist can "Win" is by breaking the old man mind in his girlfriend body by keep fucking him. And when the old man crave for his dick just say he need to give him the potion first. This is why you need to read a lot of doujin so you can anticipated this kind of situation.

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@TrustableBackstabber
Seems like the old man needs to keep drinking the medicine in order to maintain his soul in the body judging by the last pages.
So ideally, you just need to keep fucking her past when he has to drink it again.

Boom. You get your girlfriend and her body is already used to your cock.

Base +7, Haerane -10, MyraLune -7, Riddik11 -7, noahb3 -7, Luke2009 +6, venom17 -6

Why doesnt he switch bodies with the guyfriend?

Base +9, Luke2009 -6, venom17 -6, Belgaesh +6, Man Moon -6, liberius +6

Yeesh, at least the switch doesn't seem to be permanent.

Base +7, rockball +6