The Reincarnated Prince Never Fights Alone!

A story of a random guy who, for some unknown reason, found himself reincarnated into the RPG game's main character, the crown prince Zarba Altra Zigma of the Great Golden Empire. His reincarnation is, of course, coming along with a cheat, as the mysterious Spamming Summon System (SSS) that can spam summon units endlessly now becomes his number one tool for drowning his enemies alive with bodies. Well, usually, the protagonist will have to do his best to survive and deal with countless external and internal problems of his empire, including his father, the mad emperor, but being the pragmatic man that he was, the reincarnated prince just went, "Nah, I'm good!" and decided to abandon his empire to its doom instead! This is not the story about the struggle of the protagonist to hold his crumbling empire together but a story of a normal selfish man who is just trying to live his second life in peace within this fantasy world of swords and magic. ÷×÷×÷ What to expect in this story: an adult MC from the start, an MC decently strong from the start, a very pragmatic MC, a lot of summons, a slave harem but also a non-slave too, a pretty lighthearted story, no cheap drama bullshit, the author's unique sense of humor (lol), the MC already in a relationship with the main love interest (you can say they are a power couple, I guess?), mature (ecchi, not smut) scenes, and not a lot of info dumps and world building (there is some but not much). The chapter release schedule is unavailable at the moment. I just started my new job, sorry. English is not my first language, so expect some grammar, but it should be minimal enough that you can ignore it.