Roman -my dear boy-
Author: Tsunku
Arrangement: Suzuki Shunsuke.

This song rocks 

Intro
C-7  C11  (x6) 

Theme
C-7    AbM9   Bb6 (add9) (x2)  C-  Bb(7)

Verse

Eb  Bb/D C- Ab Bb
C- BbAb         Bb (x1333x@1)Eb  Bb/D  C- Ab Bb
C- Bb G C-      (Eb/G)*

Prechorus
Ab (xx1114@1)Bb7 (x13131@1) 
Eb (x43121@3)Bb/D (x1033x@1) CAb  D (xx0232@1)G (320003@1)Bb7 (x13131@1)Chorus
Eb (x43121@3)D7 (xx0212@1)G-  G-/Bb C (x32010@1)Ab (xx1114@1)Bb (x1333x@1)Eb (x43121@3)GAb GBb 
Eb (x43121@3)D (xx0232@1) G-  G-/Bb CAb  Bb (x1333x@1)C- (7)
Ab  Bb  Csus4 C  Csus2 C-

Solo
Ab Bb5 (x2)
C- (/F)  
Ab Bb5  G  Bb (7)

Repeat Verse, Prechorus and Chorus

Final chord: AbM7

Hints: 
Bb6add9: 6x556x
Bb6:  6x576x
C11: x3333x

* you'll have to wait until last downbeat of the measure to play this chord.