Ho Yay / Batman: The Brave and the Bold

• "Menace of the Madniks!" is basically a Ho Yay Love Triangle between Ted Kord and his two friends, Batman and Booster Gold. That may just be a Fandom Nod, since Ted looks slightly awkward all the times Booster hugs him.
• There's a tiny bit between Batman and the Red Hood, mostly on Batman's side. Which is pretty poetic considering of whom Red Hood is the alternate universe counterpart.
• In Requiem For A Scarlet Speedster the Flash/Barry Allen's Rogues - Captain Cold, Heat-Wave, and Weather Wizard - all seem to miss him and miss fighting him, letting out sighs of longing as they remember him after comparing him to Batman, whom they consider a disappointing substitute for Flash himself - and Batman himself calls them out on it. Whenever they think Flash/Barry has returned they react like a bunch of stalkerish fans, only to express similar disappointment when it turns out to be either Jay Garrick or Wally West. When Barry finally does return at the end they're practically jumping for joy, Weather Wizard even saying "Oh I promised myself I wouldn't cry!"
• Huntress and Black Canary are a little playful with each other in "The Mask Of Matches Malone", whether it's exchanging witty dialogue or the occasional glances to each other. There's also Poison Ivy's Amazon Brigade with her Flower Children in the teaser in that same episode.

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