Just why????

is 13RW even that good?

I guess it depends on what your into. I didn't really find it interesting, but some people did.

I don't know if they're hidden, but here are some good ones...
http://www.mangago.zone/read-manga/missing_code/
http://www.mangago.zone/read-manga/soba_ni_oitene/
http://www.mangago.zone/read-manga/calorie/
http://www.mangago.zone/read-manga/himegoto_asobi/
http://www.mangago.zone/read-manga/sono_te_no_netsu_wo_kasanete/
...and they're all complete

http://www.mangago.zone/home/mangalist/56720/

http://www.mangago.zone/read-manga/hanaya_no_nikai_de/ (does get emotional in the 2nd ch but it has a very up lifting end and there's more in the series but this one was my 1st read and favorite {I did cry, so read later after feeling better, but its a great story})

http://www.mangago.zone/read-manga/desert_moon/

http://www.mangago.zone/read-manga/shingeki_no_kyojin_dj_nyanko_heichou/

http://www.mangago.zone/read-manga/teiou_no_amai_wana/

http://www.mangago.zone/read-manga/aitsu_no_daihonmei/

http://www.mangago.zone/read-manga/anitsuu/

http://www.mangago.zone/read-manga/saa_koi_ni_ochitamae/

http://www.mangago.zone/read-manga/kokoro_kanda_neko/

http://www.mangago.zone/read-manga/sore_wa_yappari_ai_kamone/

http://www.mangago.zone/read-manga/monster_master/

http://www.mangago.zone/read-manga/jappa_no_amane/

http://www.mangago.zone/read-manga/samishigariya_no_love_letter/

the book itself was great, the series however has extra stuff which isn't bad... it's more dramatic in a sense, whereas the book it just teaches you a lesson context wise. the series does have context as well, but for me it seems it more distracting with all the drama surrounding it.