Lucas died from a cardiac arrest, alone in his room where he isolated himself for 15 years. His life was so pathetic, even a Goddess took pity on him and sent him to another world, but his worth was low that he ended up becoming a chair.
However, he was given a chance to mentor the Child Queen of a Kingdom that was stuck in poverty. It's a dream come true for him, having played tons of video games about ruling nations. He couldn't ask for anything more in this new life of his.