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Aaargh! Every update of this one makes me ride the emotional elevator... Since both title and cover make me think at first that it's Tomogui ( http://www.mangago.zone/read-manga/tomogui/ ) that has a new chapter... the deception...
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Book 1, A - With Grand Words, The Sky Falls
https://myreadingmanga.info/pataratonage-car-durarara-dj-daigensougo-de-sora-ga-ochi-eng/
The beginning of their relationship during high-school.
Book 1, B
https://myreadingmanga.info/pataratonge-kuruma-durarara-dj-taigen-sougo-de-sora-ga-ochi-eng/
There's talk about how a girl threatened Shizuo with a false pregnancy and their break up, and Izaya breaking up as well a week after that.
Book 2 - Wild Rumors Divide the Sea/Groundless Rumors Fly Past
http://www.soltarination.org/ryuugenhigo-de-umi-ga-ware-wild-rumors-divide-the-sea/
Izaya became entranced with making the above-mentioned girl suffer through a rape-like experience, framing Shizuo before going AWOL.
Book 3 - I Will Cross Yomotsu Hirasaka With You/Hell Versus Heaven
http://www.soltarination.org/yomotsuhirasaka-kimi-to-koe-i-will-cross-yomotsu-hirasaka-with-you/
With information he obtained from Shinjuku, Shizuo came to search for Izaya for almost one year and a half in the district near the seashore.
Book 4 - The Sun Continues to Rise
https://myreadingmanga.info/pataratonge-ore-ebisu-durarara-dj-rakurakurairai-hi-ga-noboru-eng/
Begins from the hotel near the seashore district, where Izaya had escaped to.
Extra - Good-bye Blue Bird
http://www.soltarination.org/good-bye-blue-bird/
Told from Izaya’s point of view.
Could someone explain to me what were (cf. summary) the 'middle-school girl's lies'? i didn't really get it but want to as I'm sure it's an important part of the story...
Me too I mean what did she mean by liar? Is it about actually wanting to see him? or something?
Lying about not needing icchi to visit
I think
I see that would make sense.