Drug Devourer is a Manga/Manhwa/Manhua in english language, Action series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

One day, a gate suddenly opened in the heavens, bringing with it the invasion of monsters and the intervention of monks in the human world. 『Miracle Drug “Coffee” Administration』 『Medicinal Contents: Caffeine and Sugar』 ☞ Provides energy ☞ Stimulates the central nervous system ☞ Maximizes senses and reflexes The whole world appeared to slow down, and Hanyul’s medications began to show their true effects.