An S-class Adventurer, Banished as the Tank of the Party, Uses His "Slave Release" Skill To Build the Strongest Country in History! 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

Alex, a holy knight, is suddenly expelled from his adventurers' party.

He tries to live a comfortable life by accepting a quest to cultivate a remote area, but suddenly he is given the extra skill "Slave Release"...?

Summon beautiful girl slaves and cultivate a demon territory overrun with demons! A slow life of harem in a fantasy world is about to begin!