World Piece, Vol. 2 (manga)

Lucas Densen and his new friends have uncovered an evil scheme to shrink planets for consumption. Yet they still have no idea how to reverse the process and restore Earth. Following a fresh lead, Lucas, Lully, and the mysterious Mitton board a space cruise in search of Dr. Caws, a scientist known to be working on a possible solution. But there are hidden threats lurking on board, and the trio may face more danger than they bargained for!