Xenomorphs (Fictitious characters) -- Juvenile fiction. Extraterrestrial beings -- Juvenile fiction. Human-alien encounters -- Juvenile fiction. Twins -- Juvenile fiction. Space colonies -- Juvenile fiction.

Princesses -- Juvenile fiction. Impersonation -- Juvenile fiction. Kidnapping -- Juvenile fiction. Extraterrestrial beings -- Juvenile fiction. Human-alien encounters -- Juvenile fiction.

Human-alien encounters -- Juvenile fiction. Kidnapping -- Juvenile fiction. Space warfare -- Juvenile fiction. Princesses -- Fiction. Impersonation -- Fiction.

Impersonation -- Juvenile fiction. Princesses -- Juvenile fiction. Mistaken identity -- Juvenile fiction. Arranged marriage -- Juvenile fiction. Kidnapping -- Juvenile fiction.

Teenagers -- Juvenile fiction. High school students -- Juvenile fiction. Superheroes -- Juvenile fiction. Ability -- Juvenile fiction. Extraterrestrial beings -- Juvenile fiction.

Teenage boys -- Juvenile fiction. Human-alien encounters -- Juvenile fiction. Extraterrestrial beings -- Juvenile fiction. Life on other planets -- Juvenile fiction. Science fiction.

Teenage boys -- Juvenile fiction. Human-alien encounters -- Juvenile fiction. Extraterrestrial beings -- Juvenile fiction. Slavery -- Juvenile fiction. Machinery -- Juvenile fiction.

Teenage boys -- Juvenile fiction. Human-alien encounters -- Juvenile fiction. Science fiction. Young adult fiction.