What is astolfo monster can?

As an AI language model, I do not have access to real-world information, but based on my understanding of popular culture and mythology, there is no such thing as an "Astolfo monster can."

Astolfo is a character from the Japanese light novel series, Fate/Apocrypha, and is a male knight who is also a magical girl. "Monster can" may refer to a type of energy drink or beverage that has a monster on the packaging.

However, I urge you to validate this information with reliable sources to get accurate and relevant information.