It's a shame Shonen Jump had to end this early same with super smartphone. These series could have been really good but just didn't have enough time to finish.
Part of the appeal is seeing all the various types of aliens. There's also a little bit of humor, some of which comes from subverting the expectations of an action-manga by having some of the interactions be resolved through bureaucracy instead of through fight scenes. The fight scenes and other action scenes are drawn well enough and the various superpowers and high-tech equipment also allow for a little bit of freshness for how the fights play out. The characters are largely whatever so far. They're alright, but are lacking the x-factor of the most memorable and iconic characters out there.
The world-building comes across as a little bit half-baked at the moment. Like, how did the "alien area" get established and why are human law enforcement agencies able to force aliens to comply with human laws? And why are some humans (like Sharaku) able to use alien technology better than aliens?
[Reviewed at chapter 11]
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 earth and the people he holds dear. Tatsumi must awaken and work with the alien police department to keep those alien immigrants in check.
So basically aliens exist hidden among humans. There is an alien police department which keeps these alien activities in check. It's more like men in black movie even some of the gadgets they use are same. Main character is kind of overpowered but he takes a bit of time learning his moves. Side characters are brimming with life and are written well. This story has also some cute elements in it. Art is also cool and it upscales during fight scenes. It is a must try for all scifi genre fans.