trademark lilies. The artwork has drawn much attention on tumblr, where the fanservice is driving the magazine's audience wild.
The inclusion may seem unusual for a girl's anime magazine--Otomedia is not the type to normally showcase hobby anime. However, other information suggests that this can be seen as a response to Vanguard's actual viewership.
At the Big Vanguard Fest this May, bracelets, hair scrunchies and T-shirts designed for women were sold; Yonaga Tsubasa and Satou Takuya featured them on their night-time radio program, Tachigare! Bokura no Vanguard, a general-audiences Vanguard talk show.
Yonaga and Satou are Aichi and Kai's voice actors respectively, and are known to go out of their way for their female fanbase, breaking out during certain parts of the program with in-character lines like "You're the one I want!" and "I'll protect you!" (They also designed the joke cards, Takugal and Eternal Wing, based off of themselves. Takugal gains a special power boost from being boosted by EW.)
Supporting these recent developments, several women's-only double-elimination tournaments are being launched in Japan, with the most recent one currently reaching across 14 of Japan's 47 prefectures. As this is coming about in the wake of female pros like Kakuhara Misaki and Asano Ami rising to prominence in regional events, the push to expand Vanguard's target demographics is likely no coincidence.