CSM interaction models compared to the light curve of OGLE-2014-SN-131 and the I band SN Ibn template. The only difference between the two models is that the latter (red line) had its ejecta mass and CSM mass reduced by 85% and 65%, respectively. No other parameter has been changed. Since we do not know the average I-band bolometric correction for a SN Ibn, we also plot the 1-sigma I-band template with ±1.0 mag bolometric correction. The model would still be consistent with the template after we apply this bolometric correction, if we allow the explosion energy to change by ± 30% (see Sect. 6.3).