I'll give that explanation.
First;
Romance
This seems a bit general. Cheesy romance doesn't just exist in anime. If anything, it's probably more of a western invention than a fairly modern Japanese one.
The clothes
This probably has more to do with Japanese ideas, not necessarily anime ones. I don't think I've seen a hood under a long coat even once in Naruto, except for maybe with Kabuto after he got all messed up. Long coats also happened to be worn a lot in fifties and sixties movies, I believe. Not to mention every time I see one of those old CSI shows... don't remember which one, though. Or was it even CSI? Not sure. ''Lady's outfit is the total anime trope of dressing less for more.'' Yeah, that has nothing to do with anime. Perhaps it does exist in a lot of anime shows, but then, it also does in a lot of other things, right? Dante, well, I suppose that one's plausible. Still, there might just be as many anime characters who wear normal clothing and have a normal hair color as there are characters who have colorful intricate clothing and wacky, colorful hair.
Music
''I know I shouldn't judge the gender of music and it's not like there were japanese vocals in DMC4, but the music really tuned down from it's loud and in your face power that DMC3 had. It sort of toned itself down to a more anime like vibe with it's battle music and the rest of its music in fact. Though I did like standard daytime. That was chill. Anywho, I like anime ost, but you gotta admit some of DMC4's music was something anime themed.''
Toned itself down? Really? In DMC4 as opposed to DMC3? I thought it was pretty much the same, at least, in battle it seemed to be. Kyrie's singing sounded like a German classical music composer's pieces, I believe. Then there was Shall Never Surrender. Most of it was pretty 'in your face'.
Lines
This one was a no brainier that this game was anime based. Most of the lines were definitely anime based. Most lines in anime take from western movies and every now and then from older movies as well. Here's a few I found.
- "Audios, kid." *Adios
-"So much for a small banter." *so much for friendly banter.
-"Fire's bad for the complexion. I burn easily and get a tan." *I burn easily, never tan.
-"Now that's a solid performance from an old fart like you."
-"Baby yeah!"
-"Nice!"
-"Sweet!"
Fixed some stuff.
I don't know why you think that's typical of anime. Sure, it may be in some anime shows, but I watched Bleach, Naruto and Fullmetal Alchemist and never heard any of those one-liners, or any others.
All in All
''People can try to deny it all they want, but in the end, DMC4 is anime styled. If you go to anime sites, DMC4 will be there. If you go to Minitokyo, DMC will be there more then DmC because DMC is more anime based. If you go to zero-chan DMC4 will be there, why? Because it's close to anime styled.''
Maybe it's more because of it being a Japanese thing. DmC was created mostly by Ninja Theory, a British developer. I guess it is anime-styled, but many of your points fall flat. No offense, of course.