コトバアワス (pronounced "KOTOBAAWAS") follows the publisher's earlier game 大怪獣コトバモドス (Dai Kaiju KOTOBAMODOS), the name of which combined 言葉 (pronounced "kotoba" and meaning "words") and 戻す (pronounced "modosu" and meaning "revert"). "KOTOBAAWAS" comes from combining 言葉 (kotoba/words) and 合わす (pronounced "awasu" and meaning "match against"), thus as you might expect this is a word-matching game.
More specifically, it's a legacy-style game that you can play only once. As the publisher suggests, "Gather two to five players, open the envelope, then play by following the instructions inside." He clarifies that this is not an escape room-style, puzzle-solving game.
Description from the publisher:
一度きりしか遊べないゲームです。
2～5人を集めて、封筒を開けてください。その後は封筒に指示に従ってゲームを行います。
謎解きゲーム（脱出ゲーム）ではありません。