JSFiddle - React, Tailwind, and code Playground

HTML

<div class="person person_3">
    Sean
</div>
<p>Hello</p>

JavaScript

Element.Properties.person = {

    get: function() {
        var id = this.className.match(/person_(\d+)/)[1];
        if(id) return Person.getById(id);
    },

    set: function(person) {
        this
            .addClass('person')
            .addClass('person_'+person.id)
            .set('html', person.name);
    }
};
$('TestPerson').get('person'); // returns Person instance of ID 3.
$('OtherTest').set('person', new Person('John')); //turns the paragraph into a person
// <p class="person person_4">John</p>