Shugo Chara!

Amu Hinamori is a 5th grade transfer student who is fashionably cool, tough and independent. Despite this, she is also a girl who seems unapproachable, both at home and at school. In reality, the "Cool and Spicy" role she plays is just a facade that she unconsciously plays. With her guardian characters, she fights the Easter Company who is extracting people's eggs to create X Eggs & X Characters in search of a special egg called the Embryo.

(Source: Crunchyroll)