I'd have to agree with you (@That3rdGuy), but only to a certain degree. Yes, the series unfortunately starts out with a pretty generic set up: Average high school boy is approached by mysterious girl who introduces him to a world of magical powers and beings and whatnot.
To name a handful of the top of my head: Omamori Himari, Witch Craft Works, Shakugan no Shana, Isuca, Holy Knight, Princess Lucia, Trinity Seven, Akuma no Ikenie, Kyou no Cerberus, Haru-nee ga Boku ni xx Suru Riyuu, and Hell I'd even throw in Bleach. Almost all of these examples are ecchi romcoms, with most having a harem attached to them, and so yes, Shishunki na Adam can easily lump itself together with the rest of em.
However, I wonder if you bothered to read past the first chapter (if not, I wouldn't blame you for abandoning ship when presented with such an overdone way to start the series), because I disagree with later parts of your comment:
Just pathetically and annoying cliches mashed in with even more pathetic and annoying fan service with minor tweaks and rearranging. Borderline H...
"...Even more pathetic and annoying fan service?" Well, actually, if there's one thing that this series managed to pull off that the other ecchi romcoms did not, it involves featuring sexual interactions between characters, especially including intercourse, and a willingness (his power makes that part debatable, but I'll explain that later) to do so.
Does that mean that this is a far superior series than all the others, simply because it has elements of a Hentai thrown into it? Unfortunately, no. I simply just wanted to point out something you didn't mention in your review/comment, as I don't see a ton of similar series having any sexual interactions of any kind in their manga, unless they're pretty much "seinen-disguised" Hentais filling out a "one-sex-scene-per-chapter" quota. (I'm looking at you, Blade Play and Ookii Onnanoko wa Daisuki Desu ka?!)
Anyway, main character has power to control an entire gender of females, as they become relentlessly lustful towards him after locking eyes (I wonder if lesbians and asexuals would be affected... [shrug]). For me, I at least find it a bit interesting to run with as a supposed "world dominating power that everybody's after." So far, he's chosen not to use it at all, due to him being a very strong believer in the power of friendship and innocence, and every time he's used it was by accident, or by somebody unleashing said power. It would be interesting to see him use his power against any female opponent trying to hurt/capture/kill him, yet either in a comedic or quite serious portrayal, he resultantly feels incredibly awkward about his opponent(s) now lusting after him, willing to submit to his every command. I'd really like to see that happen at some point, and I still think that it has the potential to pull it off. Otherwise though, nothing else noteworthy to the current plot has come out of this series thus far, aside from
the unexpected loss of virginity right away by chapter 4, and it's surprisingly not the heroine taking his first time; yet instead, it happened to be the adult angel supervisor... huh...
TL;DR: This series has sex shown unlike a lot of others out there, but still rubs off as pretty generic as far as cliches, story, and especially artwork go. Chapter releases have been pretty slow over the months/years, only to wait for not much development to come out of new chapters, so do bear that in mind when considering to pick this one up.