Summoning from the Divine Dimension

I love beautiful women and summoning. I can conjure fireballs and unleash forbidden spells. I've even summoned a Gundam to beat up little monsters. I've kicked the principal's butt, tugged the king's beard, and even felt the Dragon King's chest. I'm not a summoner, and I'm no Dark Lord. I come from Earth. I'm a divine envoy! Where the king's sword lies broken, the song of victory plays on forever. When the demonic dragon returns, so will the king! The story begins now...