Oga VS Furuichi (volume)

is volume 20 of the Beelzebub manga.

Contents

 * 171. Furuichi VS Shinki!!
 * 172. Furuichi VS Tōjō
 * 173. Oga VS Furuichi
 * 174. Tatsumi-kun and Takachin
 * 175. Damn Strong Already
 * 176. The Season's Already Winter
 * 177. Christmas is Coming!!
 * 178. Christmas is Coming!! Part 2
 * 179. The Curtain Rises! Saint Saint X'mas!!