Evangelizing (fukyou)
Overview
Fukyou (evangelizing) originally refers to spreading a religion's teachings, but on today's social media it's used to mean "recommending the things you love to others and spreading the word." As in "evangelizing my oshi" (oshi: the favorite you passionately support) or "I want to evangelize this anime," it describes recommending something with a lot of passion.
A strong word like evangelizing shows just how intense the passion behind the love is. It's not just a "recommendation"; there's a feeling close to a sense of mission: "I have to spread how wonderful this is to the world."
Question boxes and evangelizing
Question boxes are sometimes used as a place to evangelize. In response to a question like "What X would you recommend?", the person answering talks about their favorite at full passion. The answer gets shared with followers, and new fans are sometimes born. A question box looks like a one-on-one exchange between the sender and the person answering, but it's actually also a place to evangelize to your followers.
On the flip side, senders sometimes send questions in order to evangelize. "Do you know X? It's seriously good!" This is evangelizing in the form of a question. If the person answering goes along with it and replies "I'm curious, tell me more," the evangelizing has worked.
Evangelizing etiquette
Evangelizing is fun, but overdoing it can backfire. Going on and on about your favorite when nobody asked, tying every question back to your favorite, pushing it with "if you don't know X, you're missing out on life." These aren't evangelizing; they're a hard sell.
The basic rule of evangelizing is to match the other person's interests. When someone in your question box asks "What are you into lately?", talk about what you love in an appealing way. Explain "why you love it" and "what makes it interesting" in your own words. Don't push; show its appeal. Leave it to the other person whether they get interested. Keeping this kind of distance decides whether your evangelizing goes well.