Why didn't Yosef, who was extremely strong (as the Midrash describes in Vayigash), grab his cloak from his mistress before fleeing?
Ramban: Out of respect for his mistress.
Oznayim la'Torah: It wasn't from his mistress that Yosef was fleeing but from the Yeitzer ha'Ra. 1
As Chazal said in Avos 1:4
Why does the Torah write say "va'Yanas va'Yeitzei" (he fled and went outside)"?
Seforno: Yosef initially fled from the room in order not to be overcome by the Yeitzer ha'Ra. Once outside, he walked, to avoid suspicion that he had done anything wrong. She did not know this, and assumed that he would tell people that he fled due to her seduction.
Hadar Zekenim: "va'Yetzei" on the merit of "va'Yotzei Oso ha'Chutzah" (Bereishis 15:5-6 - and Avraham believed).
As the Pasuk writes in Tehilim "ha'Yam Ra'ah va'Yanas!" See Oznayim la'Torah as to why the merit extended to the whole of Yisrael.
Why does the Torah add the word "Leimor"?
Peninim mi'Shulchan ha'Gra: When she saw that he refused, she told him 'say "lie with me."' This would make him more prone to sin. Above (verse 7), "va'Tomer (she said) Shichvah Imi." 1
Or ha'Chayim: This was her intent. Actually, she did not say anything. She only grabbed his garment to force him.
This explains why it says here "Shichvah" in the feminine. However, it does not explain why it says "Shichvah" also in verse 7. (PF)