To The Future「未来へ Mirai e」 is the 344th chapter of the manga, Nanatsu no Taizai.
Q394. Yeti-san (From Yamagata Prefecture): At what age do Giants start training to battle?
Nakaba: About right after they can stand up on their own.
Q395. hsu-san (From Taiwan): Would Diane be unable to shrink freely once Merlin disappeared?
Nakaba: Right. But since she's originally a huge Giant girl, she should do fine.
Q396. Nachan-san (From Ooita Prefecture): What kind of person is Merlin's mother?
Nakaba: It's a mystery.
Q397. Elena-san: Do Fairies have wedding customs?
Nakaba: They don't, that's why if they hold a wedding ceremony, it will be a discovery for King and Diane!