If I'm not mistaken, "renchin" is a pun based on "錬金術" (alchemy) and "レンチン" (microwave oven). The "ren" part in the latter comes from "range" (stove), and "chin" is from the sound. https://word-dictionary.jp/posts/1009
Damn, things are stepping up.
Will really got a well-rounded education, but only now he realizes how everything applies in real life. Really like his introspections.