Talmud: Tractate Kiddushin class by Rabbi Yoni Handwerger שליט׳א
Part 19
The bulk of tractate Kiddushin discusses the laws of betrothal and marriage. The last few pages of the tractate delve into the laws of yichud, the prohibition against an unrelated man and woman (unmarried to each other) from secluding together. On a related note, the Talmud discusses various professions that should be avoided by bachelors, because they call for extensive dealings with members of the opposite gender.