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tokens: Local Bubble. By analogy to the λ 5780.5 carrier, which appears to be a cation from the dependence of its EW on the ambient UV radiation field (Cami et al. 1997 ; Sonnentrucker et al. 1997 ; Vos et al. 2011 ), we suggest that the family of NIR DIBs also arises from cations. This idea is compatible with the DIB-PAH hypothesis, which proposes that the ionized PAHs are the carriers that have their transitions in NIR wavelength range (Mattioda et al. 2005 ; Ruiterkamp et al. 2005 ; Cox et al. 2014 ). Recently, in the first conclusive identification of DIB carriers, two DIBs at λ = 9577, 9632 Å were assigned to the absorption features of interstellar ionized buckminsterfullerene () (Foing Ehrenfreund 1994 ; Campbell et al. 2015 ). Ionized fullerenes and their derivatives are also expected to be the carrier sources of NIR DIBs. In Section 5.2 , we suggested that the λ 10504 carrier is destroyed by the ionizing photons in Cyg OB2, whereas those of the family DIBs can survive the Cyg OB2 environment. We also suggested that the λ 12623 carrier may be produced in Cyg OB2 (Section 5.2 ). The destruction of the λ 10504 carrier and possible production of the λ 12623 carrier are probably caused by the strong UV flux in the Cyg OB2 environment. The different environmental dependence of these two DIBs and the family DIBs would be due to the difference of their carrier properties, such as the ionization state and the stability against the UV photon flux. The FWHM of λ 10504 is ∼1.2 cm −1 , which is one of the smallest widths among 17 DIBs investigated in this paper, whereas the FWHM of λ 12623 is ∼2.4 cm −1 , which is one of the largest. If the profiles of the DIBs are unresolved rotational contours, the widths are mainly determined by the rotational constants of the carriers (Cami et al. 2004 ; Oka et al. 2013 ). Assuming that the geometries of the molecules are similar, the band widths of the smaller molecules should be broader due to the larger rotational constants. Therefore, the λ 10504 carrier would be larger than the λ 12623 carrier. Then, we speculate that the photodissociation of the λ 10504 carrier results in the production of λ 12623 carrier. 6. SUMMARY We investigated the environmental dependence of DIBs toward Cyg OB2 using WINERED spectrograph data. We observed the seven brightest OB stars in the J band in Cyg OB2, and detected all known NIR DIBs with large EWs toward all observed stars in the wavelength coverage of WINERED. Our findings are summarized below: 1. Five of the DIBs ( λλ 10780, 10792, 11797, 12623, and 13175) are well correlated, suggesting similar physical and/or chemical properties of their carriers. 2. The EWs of DIB λ 10504, which were suggested to be well correlated with the family of NIR DIBs in Paper I , are almost constant toward Cyg OB2. In contrast, the EWs of the family of NIR DIBs vary by a factor of two. We attribute the different behaviors of the DIB λ 10504 and the family to the environmental sensitivity of the DIB λ