na-adjective
geeky; otaku-like
Slang adjective describing someone or something as having the obsessive, niche interests characteristic of an otaku. Often used self-deprecatingly or playfully.
See also: オタク
彼の部屋はフィギュアだらけで、ちょっとオタッキーだね。
His room is full of figurines, so it's a bit otaku-ish, isn't it?
そのアニメの知識はすごくオタッキーで、ついていけないよ。
Your knowledge of that anime is so geeky, I can't keep up.