Really, really funny.
The characters are funny, the premise is zany, the writing solid, and it has just the right amount of sincere heartfelt emotion to make it something more than just a series of comedy skits.
I never thought I'd find a manwha funny enough to laugh in every chapter, but here it is.
What are you staring at a review for? Go read it.
(For the sake of making word count, I'll just correct the assumption that the main character is a mechanical engineer, as he is clearly a civil engineer/architect. One of the translations had him pinned to mechanical, so I just wanted to clear that up)