Heavy Dependence on Potions

My name is Ireno. When you see my suicide note, I might have rowed on the River Styx Why do you say? Oh, yes, I traveled to another world, but the style of my other world is a bit unusual... What does it mean that drinking life potion can only increase the upper limit of blood volume? What does it mean that I can only fight enemies with a higher level than myself? What does it mean that I can only get a one-day experience card after drinking the magic potion? Since then, I have embarked on a path where there is no sense of security without the magic potion. But, you know, the end of this road is either becoming a magic potion or becoming a monster...