User blog comment:B214/Volume 23 discussion blog/@comment-31764731-20170419212431/@comment-23853100-20170420014937

Well Sirzechs not having a harem might be due to political and personal consideration.


 * 1) The top brass politicians may intend to wed their relatives to gain some political advantage and to tie down the Maou. For example, the Barbatos head may purposely wed his sister to Sirzechs to compel Sirzech into helping him out as a brother-in-law.
 * 2) Sirzechs doesn't want the Gremory to be affected due to his status. Sirzechs may be a Lucifer now but he is also a Gremory, unless of course you're claiming Sirzechs is no longer Zeoticus' son or Rias' brother. So any relation to Sirzechs will somehow be linked back to the Gremory, people still link Ajuka to the Astaroth clan because he came from there. If Sirzechs partakes in political marriages and obtain some connection with other clans, it will somehow be linked to the Gremory. That may cause issues for his father, Rias and Millicas after all they are undoubtedly Sirzechs' family.