A few days ago, I was looking through the forums and found this one thread, where this one member was looking for Maid Mangas, then one person made a suggestion and I liked the manga. I forgot the title of the manga though.Heres from what I remember:

The guy is considered the heir even though he is just a son of a noble [i think?] and his mistress. Then one day,this girl shows up and tells her he's her servant or maid/protector. She protects the guy using her mop. From what I remember, the girl on the picture is blonde, wears glasses, hair in to pigtails and she's pretty [I don't know if that helps,but...]

Thank you for the help ^______^

It should be Kimi wa Boku no Toriko nare.