Traveling Through Thirty Years of Primitive Society

If you knew you were about to travel back in time to primitive society for thirty years, what would you choose to bring with you? Thirty years later, it's not too much to buy a few girlfriends online and take them with you! What? There's no space to fit it in! It seems that I can only bring some necessities. Ah Wei thinks that his girlfriend is a necessity. It must be fun to come back after thirty years. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.