Takarakuji de 40-oku Atatta n dakedo Isekai ni Ijuusuru  

宝くじで40億当たったんだけど異世界に移住する

Kazura purchased a lottery on impulse and won 4 billion yen. To escape the hyenas that detected the scent of his wealth, Kazura sought refuge in an ancient family residence that had been passed down through generations. While exploring the property for a suitable shelter, Kazura discovered a particular room that allowed him to travel between worlds. The technology and culture of this world were relatively underdeveloped. In this realm, he would discover his true worth as an individual.