Old/dilf ml

http://www.mangago.zone/read-manga/tsuiraku_jk_to_haijin_kyoushi/
http://www.mangago.zone/read-manga/ojou_to_banken_kun/

MLs dont look that old but the age gap is real

http://www.mangago.zone/read-manga/lover_boy_lezhin/

These ones are BL that feature an older male:
http://www.mangago.zone/read-manga/kiraware_joushi_to_perfect_buka/
http://www.mangago.zone/read-manga/saenai_oji_san_to_ore_sama_yankee_kun/
http://www.mangago.zone/read-manga/my_father_in_law_is_my_wife/
http://www.mangago.zone/read-manga/koishite_daddy/
http://www.mangago.zone/read-manga/nichijousahan_bi_beautiful_life/

Here some
http://www.mangago.zone/read-manga/koi_ga_ochitara/ (my absolute favourite)
http://www.mangago.zone/read-manga/kirei_ni_shiteyo/
http://www.mangago.zone/read-manga/suki_ni_nattara_dame_desu_ka/
http://www.mangago.zone/read-manga/come_to_hand/
http://www.mangago.zone/read-manga/love_awakening_x_syndrome/
http://www.mangago.zone/read-manga/how_sweet_is_a_sugar_daddy/ (I really like this one too)
Hope you'll enjoy reading them

http://www.mangago.zone/home/mangalist/1114094/
http://www.mangago.zone/home/mangalist/609078/