Boss Is Super Strong, But A Coward is a Manga/Manhwa/Manhua in english language, manhua 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

Protagonist who traveled through another world turned into a skeleton solider. The male protagonist is a novice. The hero is full of protagonist halo and various buffs. Protagonist aura , max critical damage, hyper luck! Amazing! Hero OS: Master looks at me so terrifyingly! Is he going to eat me! ! Great Demon King OS: It’s a hero! ! Go away! don’t beat me up!