Do you usually read your favorite stories more than once? Like, if they are complete, you ...

Yeah I do but not the whole story tho, the parts I liked most
Mo dao zu shi is amazing (novel)

Yes, I do. Most of my faves are complete though (and the ongoing ones are well... I have issues with incomplete manga and cliffhangers that I tend to stay away from them even tho I love them, to the point where I'm not sure I should read them even when they're completed... yeah I'm weird). For the completed ones, I re-read them occasionally or when I remember them and miss them.

Here are some of my faves (that I have re-read at least once):
http://www.mangago.zone/read-manga/rutta_to_kodama/
http://www.mangago.zone/read-manga/aozora_kirai_no_usotsuki_semiko/ (not bl. I re-read this every summer just to feel the feels)
http://www.mangago.zone/read-manga/junketsu_drop/
http://www.mangago.zone/read-manga/yamete_kudasai_mabushii_desu/
http://www.mangago.zone/read-manga/lonely_to_organdy/
http://www.mangago.zone/read-manga/kimi_no_yume_o_mite_iru/
http://www.mangago.zone/read-manga/500_nen_no_itonami/
http://www.mangago.zone/read-manga/yamada_to_shounen/
http://www.mangago.zone/read-manga/hinadori_wa_shiokaze_ni_madoromu/
http://www.mangago.zone/read-manga/itou_san_kuraka_sui/
http://www.mangago.zone/read-manga/hare_no_hi_asada_nemui/
http://www.mangago.zone/read-manga/life_senjou_no_bokura/
http://www.mangago.zone/read-manga/paradise_view/
http://www.mangago.zone/read-manga/kosha_ura_no_natsu/ (this. I remember re-reading this frequently some time ago just to feel pain. im totally not an m)
http://www.mangago.zone/read-manga/kowagaranai_de_soba_ni_ite/
http://www.mangago.zone/read-manga/wakabaryou_de_kimi_to/
http://www.mangago.zone/read-manga/kimi_wa_natsu_no_naka/
http://www.mangago.zone/read-manga/koi_ni_mo_naranai/
http://www.mangago.zone/read-manga/uchi_no_tenshi_ga_kemono_deshita/

I... did not expect it to be this long. Anyway, I have more faves but those are some that I really love to the point of re-reading from time to time! :) I'll be happy if you can find one you can/like as well.

I reread the ones that are completed once in a while if I really liked them and I feel like reading them again. I also reread some when I want to read something and find one that I can't remember very well.

I also reread the ones that are not completed if they are really good or if I can't remember what happened before the latest chapters.

The ones I keep rereading even though they aren't complete are Haikyuu!! and Diamond no Ace act II

The ones I reread once in a while even after completion are Yaoi, I don't know if you're into that, but they are:
Junketsu Drop
Suzume Favorite
Soredemo Kamawanai
there are a bunch more, I just can't think of them right this moment.

hmmm, I noticed that I have a few favorites that are completed and I still like to read again once in a while:

- Choco Strawberry Vanilla by Psyche Delico
- Yoru to Asa no Uta by Harada
- Doushitemo Furetakunai and probably everything else by Yoneda Kou
- Rouge; Aka To Kuro, Hana to Junketsu by katsura komachi

The only incomplete manga that I read several times is Saezuru Tori wa Habatakanai by Yoneda Kou. I'm pretty sure that I'll be 90 years old and still go back to this one.