As the title said, I'm looking for a romance manga in which the main female lead is not being manipulated by the guy and blushes all the time. She must have strong personality, a little bit cunning and player is fun too~

Here are some examples:

Hana no Kishi (Kei~~)
Atashi Wa bambi (she knows to choose)
Devil and her love song (I didn't like the guy in this one T_T)

Spice and Wolf wins.

Switch Girl!! - heroine has quite a personality
Chotto Edo Made - although there isn't clear romance yet...but the girl and guy's personalities are almost reversed of the norm

Something like Ciel?

[img]https://i.imgur.com/lHjrfaR.jpg[/img]

second Spice and Wolf

Try Warau Kanoko-sama. It's about a "plain" glasses girl who observes the rest of her class. She's definitely strong and cunning. The only thing that I could say that doesn't really fit into your requirements is that it doesn't really focus on the relationship between the male and female protagonist.But she isn't being manipulated by the guy.

Would you like to join the Axis Order?

I think Watashi ni xx Shinasai! fits.