Minor spoilers ahead. Just skip to enjoyment if you want it completely spoiler free, although the amount isn't really that much to begin with.

Ecchi and action: a match made in heaven. Unfortunately, that's only the case if the proper set up and balance are created, which Taboo Tattoo does not accomplish. What it does do is it creates a visually sound action adventure of pervs, sadists, heroes and homosexuals.

Story: Right off the bat, the classic set up of "boy gets dragged into secret war between two sides" comes into play. Battles are not in short supply but are instead brief albeit brutal affairs with lots of blood and guts, which was somewhat surprising considering the manga can sometimes come across as juvenile with its copious amounts of fan service done is ways that disrupt the flow of the scenes and plot. That's not to say the use of sexual imagery is completely for fan-boners. Rape, suggested and not so, is used a source of shock value, as if the series is trying to prove its grittiness.

As for the series' pacing and tone, the first parts seem inconsistent, as breast fondles and sexual comedy happen while hearing exposition dumps and sometimes the manga goes out of its way to give more fanservice, changing entire characters just to pander to the readers.

Characters: On the subject of characters, almost everyone, from the protagonist, to the antagonist, fits into some sort of archetype, albeit some more snugly than other. That being said, some characters, like B.B, do a great job at fulfilling their roles, making the audience care about their struggles and pasts, while others, like the enemy Princess (who seems to be a kind of hyper-genius girl with OP powers), fail by letting the fanservice affect them. The antagonist especially actually has a decent reason for her objectives, but she loses credibility when she surrounds herself with a same-sex harem just for kicks and playfully molests the childhood friend of the protagonist after the later loses to her in a game of table tennis... As a whole, the characters are unremarkable except for a select few like B.B and Lurker.

Art: Art is meant to supplement the story and for the most part the artwork of the manga succeeds in this respect. Illustrations can have a sketch like quality on a few occasions, but the well-paced battles exhibit the artistic chops of the illustrator. The character designs and backgrounds are a tad on the generic and unremarkable side, made painfully obvious by the characters themselves.

Enjoyment: If the fanservice was dialed down or at least integrated more naturally, I probably would have enjoyed the series a lot more. Fanservice is not a pet peeve of mine, but if it interrupts the tone and pacing of the story completely, then it can turn a decent series into a lacking one. Characters are defined by their actions, not just their motivations, and this is where characters like the antagonist and other characters fall victim to the manga's immaturity. Those who like typical action manga's with guns and superpowers may find something to enjoy, but beware of the awkward tone and sluggish pacing of the first part. The series has some highs and I intend to finish it, but so far, it's below average.

Let's hope that the next few chapters fix the sins of its predecessors.