@BasicEden It wasn't the same situation, though. Did you not see the girl drink the water to show him that it was not poisoned? I mean...you realize it was the plant that drugged him that time, right? Seems to me that you're calling apples and oranges the same thing. You can't compare them. He's getting tricked in different ways that he hasn't encountered before...ways that he's ignorant to. Your analogy even shows what I mean as you give no specifics. What are each of their scams and how do they differ. That's what you don't seem to recognize is the differences in circumstance. You're just looking at the surface of the "trick" and not seeing that they are different tricks...calling them the same "trick" when they're not.
Like I said, this manhua is riddled with issues...but him falling to different tricks isn't one of them. What is one, is that everyone he meets seems to want to trick him...which is unnatural. Not everyone would want to trick someone they just met.
To further show what I mean...say you're drugged...would you forever be paranoid every time someone presented you with something to drink and never drink something someone offered to you. That's just paranoia and also shows disrespect to the person who's just trying to offer you, a guest, something to quench your thirst. Even your analogy shows this paranoia as now you'd expect the Prince of England to scam you because the Prince of Nigeria did. Again...you're jumping on the MC's case because he doesn't share your paranoia. Must be a sad life you live suspecting everyone just because someone once tricked you.