When Evans quizzed if being a "monster" was a good thing or a band thing, Styles said: "It's a good thing, he's a monster as in a musician. At midnight he just turns."
The Sweet Creature singer - who released his debut self-titled solo album yesterday - said he has no nerves about heading out on his world tour later this year, because he has made a record that he actually "likes".
Asked if he is getting nervous, he admitted: "No. Performing is my favourite. I think the thing is, I've made an album that I really like. So the good thing about that is, I feel like I am happy with it."
And, Styles seems to be a big fan of pizza as he recently sent the Italian treat to fans waiting for his performance on the Today show.
He kickstarted the programme's annual summer concert series on Tuesday, and sent the boxes of the fast food to dedicated fans who had been waiting all night - some reportedly for days - to see the star live and up close.
In a video posted to the show's Twitter page, a delivery man can be seen handing out slices of the plain cheese-topped pizza to fans huddled in warm blankets and hoodies as they braved the night air in order to get the best view of the hunky musician.
The video was captioned: "WATCH: What a guy! @harry_styles ordered pizza for fans that slept outside for days for this concert #HarryStylesTODAY (sic)"