pagan:
(also ‘paganist‘; plural: ‘pagans‘; pronunciation: the letter ‘g’ is said with a ‘g’ sound as in “gun” — for the right pronunciation, please click here)

some pagan doing pagan rituals
a person who worships several gods; an idolater;
a person who does not belong to any of the major religions — Judaism, Christianity or Islam, but has a minor religion of his/her own; an infidel;

pagans at worship
a person who does not believe your own religion or god;
a person who does not have any religion; an unbeliever;
a person who always looks for sex or sensual pleasures,
e.g.
Everybody was surprised to hear that Tom had been a pagan for quite some years.
Paganism, paganish and pagandom are some of the words more commonly used in relation to a pagan.
