What "English" word turned out to be fake English for you?

Hi, I'm a solo developer from Japan and I'm launching WaseiGo here on September 1st.

The app focuses on wasei-eigo, the 1,000+ Japanese words that look and sound like English but have different meanings. For example, an electrical outlet is a "consent". An all-you-can-eat buffet is a "viking". Cheating on a test is "cunning". These are completely normal Japanese words, and most Japanese speakers have no idea which ones are real English and which ones aren't. That's the gap the app covers. There are many pitfalls that travelers to Japan and Japanese language learners are bound to encounter.

The rabbit hole is deeper than it looks. Some words changed meaning on the way into Japanese. Others were cut in half, so "convenience store" became "konbini". Some words were assembled in Japan from English parts and never existed in English at all, such as "baby car" for a stroller. Each word in the app comes with a short illustrated dialogue, audio, a quiz, and the backstory of how the word came to be.

So here's my question. If you've studied Japanese or lived in Japan, which katakana word confused you the most? If you're Japanese, which word shocked you the most when you learned that it doesn't work abroad?