From Longman Dictionary of Contemporary Englisha creature of habita creature of habitHABITsomeone who always does things in the same way or at the same time → creature
Examples from the Corpus
a creature of habit• Probably not - I am a creature of habit.• Taurus is a fixed sign, which means you are a creature of habit and are fond of material comforts.• But I was comfortable in it, ever a creature of habit as I told you earlier. 