Aliens Area

Tokyo, Planet Earth... High schooler Tatsumi Tatsunami lost his parents at a young age and now works multiple part-time jobs to live a hectic but peaceful life with his younger siblings. One day his body undergoes a sudden change... And now mysterious beings are showing up at his house! In order to protect the people he holds dear, in order to protect Earth (or "area"), Tatsumi must awaken! He better, because "they" are already here!

(Source: MANGA Plus)

Note: Includes 1 extra chapter.