Enjoyed it quite a bit. A cute romance without the usual side-flings.
I liked the slightly laconic, deapan way the PC speaks. Fits the character. Good and believable chemistry between Mary and PC, nice mom/daughter relationship between Andy and Mary. Some abrupt cuts / scene transitions aside, the pacing is well done: not too slow, not overly rushed.
Where "Melody" has music and movie references, Life with Mary has literature. Guards! Guards! is usually my first suggestion for people starting to read Pratchett, Anna Kirinina's Levin/Kitty subplot is a good choice for classy Age Gap stories. Would like to see more of that, since it fleshes out the PC's character.
It might be a little vanilla for some of the more seasoned kinksters on here, but not every story has to be the 120 days of Sodom. Recommended.