is thr any romance??
even a hint of it??

best shonen manga couples :

shinichi X ran
natsu X erza
ippo X kumi
naruto X gaara

no

Starter of Controversy.

There is a bit between him and some biker-girl... And I think that some other female characters have seemed somewhat interested in him, but that may just be my misinterpretation.

There isn't any romantic relationship between the characters, like most shounen series out there. There's only a few female characters, which act as a pseudo harem for Kenji. And what little Kenji thinks of the female characters, is mostly of friendship... not romantic. It's as if he has no concept of a romantic relationship... Otherwise, it's pretty one-sided on any girl that may or may not like Kenji.

Wait, there is a romantic relationship... it was in the beginning between Kenji's friend and his girlfriend. They were on a date when he ran into Kenji again.

[color=green]"Officially, this machine doesn't exist, you didn't get it from me,
and I don't know you. Make sure it doesn't leave the building."[/color]

Yes. Kenji and Tony Tan.