Bottom's initial response to being offered the role of Pyramus, the male lead that commits and is in love with Thisbe, is to be quite pleased. He feels a great deal of excessive pride in his abilities as an actor, even though he has never really performed before. He feels that he will be able to play the role in such a convincing manner that the audience will be moved to tears, as we see in his lines, "If I do it, let the audience look to their eyes; I will move storms" (I.ii.22-23). However, he also feels that he would play the role of a "tyrant" better than a lover, meaning a powerful, authoritative figure, like Hercules.
In addition, Bottom is so enthusiastic about the play and thinks so highly of his skills that, ridiculously, he asks to play every major role in the play. When Flute hesitates to play the role of the female lead, Thisbe, Bottom asks to play that role as well. When Snug is asked to play the part of the lion that frightens away Thisbe, leading to both Pyramus's and Thisbe's suicides, Bottom enthusiastically asks to play that part as well, saying that he will roar so well that it "will do any man's heart good to hear [him]" (65-66). Of course this is an absurd idea of Bottom's because he would have to be on stage playing all three major roles at once. He would have to whisper loving words to himself as Thisbe and then scare himself away as the lion.
Finally, Quince convinces Bottom to not only accept the role of Pyramus, but to play only that part by explaining that only he is suited to the role as he is the best looking and the most "gentleman-like," as we see in his line, "[F]or Pyramus is a sweet-faced man; a proper man, ..., a most gentleman-like man" (77-78). Therefore, Bottom's first reaction to the role as Pyramus is that he thinks he can do the part well, but he would much rather show off all his skills by playing every single major part in the play.