Nope, this isn't a Christmas song at all, although Mariya Takeuchi（竹内まりや）has released her fair share of Yuletide tunes over the decades. However, I always feel that this is the ideal song to hear after that huge turkey-and-mashed potatoes dinner on December 25th. It's good digesting music for some reason.
Written and composed by Takeuchi, "After Years" was her 16th single released in November 1987, and the lyrics have nothing to do with Xmas, although they do talk about another sort of festive occasion...the school reunion. People are getting together after several years of being out there in the workplace, and for one woman, the moment is especially poignant as she meets an old flame for the first time in a long while. The music is sunny but relaxing with that bit of bossa, and the puffy horns kinda bring back that feeling of the 1960s, and Takeuchi knows quite a bit about the music of those times.
"After Years" got as high as No. 55 on Oricon, but wouldn't get onto an album until 5 years later when it was included on her 8th album, "Quiet Life". I've already written about it here.