I later thought that maybe someone is trying to find a counter to the Lending SkillSeems like he was trying to make it look like he was crying. Bowed down on the ground like that, Marz should've been able to see drops of clear liquid falling without being able to see that they were dripping out of that small bottle instead of the guy's eyes.
I mean, in a previous chapter it was mentioned that MC couldn't active his Lending End & Payment Skill, because his former party members mana was going berserk because of the drug he took.
I thought that maybe it's a prototype counter to MC so that when he tries to take back the lended skills and it's payment, he gets a recoil of some sort damaging MC instead.
But because MC didn't go for retrieval, the plan failed.