Ossan no Pants ga Nandatte Ii Janai ka!

50-year-old Okita Makoto is a middle-aged man who is old-fashioned and prejudiced against certain people and behaviors. Because of his values, he is disliked by his son, who likes cute things, his fujoshi daughter, who likes BL, and his wife, who is a fan of male idols. After meeting a gay young man, Makoto begins to slowly change his way of thinking..
(Source: Drama-Otaku)
~~ Adapted from the manga series "Ossan no Pantsu ga Nan Datte Ii Janai ka!" (おっさんのパンツがなんだっていいじゃないか！) by Nerima Zim (練馬zim).