The 35-year-old singer is reportedly planning to pop the question as soon as possible because their relationship feels so natural and he is convinced the 'Part Of Me' hitmaker is The One.
A friend told more! magazine: ''John really likes the fact that Katy is so independent and not needy and clingy like the other girls he's dated. This is the first time John's felt so strongly about a girl. She's played her cards perfectly.
''They really do bring out the best in each other. It wouldn't surprise me at all if he proposed.''
The 28-year-old brunette is also smitten with 'Your Body Is A Wonderland' singer John and thinks he could be the man for her after her heart-breaking divorce from Russell Brand last year.
She is rumoured to feel ready to settle down and start a family with John even though they have only been together for six months.
Another pal divulged: ''John has given her the confidence to jump out of the rat race. With John, she feels like herself. She wants to nest. She's gained a few pounds, is taking a much-needed break from work and perhaps is even getting her mind and body ready for pregnancy.''
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