Have just caught up to the anime.
First of all it is directly related with the manga Zettai Karen Children, which is currently ongoing. The thing is that the anime is being shown from Hyoubu's perspective while the manga shows stuff that chronologically are before the first episode of the anime and elaborates more with the 3 girls of the B.A.B.E.L. faction.
For reference:
If I remember correctly, in the manga you can also see the first meeting of Hyoubu with "The Children" that Hyoubu speaks of at some point in the anime.