Loved the game for ps2 and defenitely love this manga too! The characters or art might be not the best but the storyline is outstanding, played the game for 180 hours, finished it 2 times and still want more :$
Same goes for manga, though it's not full released yet, but this is one manga I'd recommend reading! You may find the beggining 'strange' but you'll kick in and even might get 'addicted' ^^