Bing found the following results
oppai Meaning & Origin | Slang by Dictionary.com
What Does Oppai Mean? - Meaning, Uses and More - FluentSlang
おっぱい - Wiktionary, the free dictionary
oppai - Wiktionary, the free dictionary
Oppai – Meaning, Origin, Usage - DigitalCultures
Meaning of オッパイ in Japanese | RomajiDesu Japanese dictionary
Anime Tiddies | Know Your Meme
Understanding “Oppai Daisuki” Meaning in Japanese – A Friendly …
Search Anime - MyAnimeList.net
Oppai - Wikipedia