nostalgic orgasm

An overwhelming recalling of happy feelings for events, products, or trends, mainly concerning the late 1980s and 1990s.

A nostalgic orgasm, fundamentally is when an individual is confronted with a bunch of items of various types (videos, video games, music, people, etc.) that all elicit nostalgia/a "sentimental longing or wistful affection for the past" (thanks Google for that) in that person (because all of these things are somehow connected to whatever that individual has experienced in the past) on a correspondingly (if not better so or less so) huge/tremendous/big/overwhelming/etc. scale, such that it resembles the overwhelmingly blissful feeling that you get when you orgasm/take drugs (which give you the feeling of many orgasms), except this particular brand of orgasm is not from sex or masturbating; it is caused by nostalgia. In simpler terms, this "nostalgic orgasm" feels like an orgasm that is caused by nostalgia on an overwhelming scale, so it is kind of different from an actual one but is fundamentally the same in that both give extreme amounts of pleasure (though they are different in their style of giving the pleasure, kind of like how Arabs and Americans are fundamentally the same in that they both are human beings who eat food, drink water, etc. but may do so in their own distinct styles).