Lahan is not shortsighted?

I have read all volumes of TAD, but where's the part where it says that Lahan only wear glasses and abacus everywhere so that Lakan recognise him instantly?

I almost post unfunny meme about people with shortsighted when I found this info on other platform. If I post it before I found out about it I'll surely be humiliated for not knowing he's not even shortsighted 😭😭 I mean, I know Lakan wear his monocle just as accessories, but Lahan?