Todita is a diminutive form of toda (all/whole). While toda is common, adding the suffix -ita makes it more endearing and emphasizes the completeness in a tender way.
In the song, the lyric "Me gustas todita completa" (I like all of you completely) uses todita to express a deep, affectionate appreciation for every single part of the person, from head to toe, in a very sweet and intimate manner. It's a charming way to say "every bit of you."
Have you ever just been completely smitten with someone, from head to toe? That's exactly what Banda El Recodo is singing about in "Me Gusta Todo de Ti"! It's a super sweet and straightforward declaration of love, where the singer just can't get enough of their special person. They start right out by saying, "Con palabras sencillas hoy quiero decirte / Me gustas de pies a cabeza" [With simple words today I want to tell you / I like you from head to toe]. How cute is that?
They go on to praise everything about this person, from their smile and eyes to their face and even "esa forma tan dulce de hablarme" [that sweet way of talking to me]. The singer feels like they made the "elección correcta al elegirte / Para estar siempre conmigo" [right choice in choosing you / To always be with me], and honestly, who wouldn't want to hear that? It's a really heartfelt song about finding someone who feels absolutely perfect, inside and out, and just appreciating every single thing about them.