I was hiding my 小马 addiction, but my Dad caught me drawing ponies about one and half 月 ago. It turned out he found my drawings earlier and wanted to see the process of creation. He 说 it's weird, but if this is what I like, he has nothing against it. It was still a very awkward moment.
To answer your question, it fully depends on you. If 你 feel to have the guts to be open about MLP, then confess. But prepare your soul first, 你 don't know how your surroundings will react. They'll probably gonna say fine, make a frown and 移动 on. 或者 你 can just 显示 them this pic, and say: Yeah... a 显示 for little girls. :)
well we always watch MLP on 你 tube in the living room (where our parents/aunts watch TV) so they could see us watch it....and its fine we didnt feel akward 或者 anything cause they liked it sometimes we when we were watching MLP we sometimes get overexcited and they hear us same when we sing MLP songs...they actually liked them with the BBBFF-they told us to sing MLP songs while they were video recording us...and told us to send the BBBFF song to my older cousin brother Axl on his b-day and he loved it! he 说 that was very sweet and 说 "awww~" and they even heard us talk about Equestria Girls (in the living room again!) about it going to theaters and all...and thats how it went with us =)